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Old 29th December 2019, 03:58 PM   #41
smartcooky
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Originally Posted by Elaedith View Post
From what I can see, they are looking at the implications of spuriously identifying a more distant relative as a close genetic relative of the target, using a protocol that is intended to target only first-degree relatives. They are suggesting that there is a fairly high probability of a more distant relative being erroneously identified as a close relative and that the protocol cannot reliably determine the kind of relationship to the offender. If only close-relatives of the match are investigated, the search is confined to few people and is relatively targeted. If the search is expanded to include more distant relatives, a large number of people with low probability of being the source could be investigated and this could resemble more of a fishing expedition than a targeted search. This could include investigating associates with no biological relationship to the original match because this is harder to establish among more distant relations. It could also result in using more intrusive measures, such as questioning or DNA sampling, to establish the degree of relatedness. They also imply that this could disproportionately affect some ethnic groups because of over-representation on the database.
I have a question for you.

Witnesses report that they see a black Chevy Suburban leaving the scene of a crime. Between all the witnesses, the Police manage to glean that the first letter of the licence plate was either "4" or "9". Black Chevy Suburbans are as common as mud, and this is a description that would match thousands of them.

Would it be appropriate, in your view, if the Police tracked down and interviewed every owner of every black Chevy Suburban in the area/city/state, or would you consider that to be a fishing expedition? Would that be imposing an undue burden on those who own black Chevy Suburbans?
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Old 29th December 2019, 10:23 PM   #42
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Originally Posted by Rolfe View Post
I don't see the problem with casting a net wide enough to catch a serial killer, whether it's questioning everyone in the county who owns a car similar to the getaway vehicle, or asking for DNA samples from everyone who might reasonably be thought could be a match to the killer's DNA - irrespective of how that match was obtained.
The police detect it was a cousin who is the criminal. One relative refuses to cooperate. Do they charge that person? Or keep on looking at other relatives? And what should they do if this turns up nothing? The person who is not cooperating might be the guilty party or they might just hate police.
Same if it was a car (as per smartcooky's post above) and not DNA.
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Old 30th December 2019, 01:56 AM   #43
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And? I'm not sure what point you're trying to make there.

There was a case in England some time ago where every male in a particular geographical area was required to give a DNA sample in relation to a particular crime. The culprit persuaded a friend to trick the system and give his DNA instead. The friend later became suspicious of the fairy-story used to persuade him to carry out the trick and went to the police and confessed. DNA was then collected from the evasive party, no refusals accepted, no arguing, and he was found to be the murderer. So I think there are ways of dealing with people who refuse to co-operate.

Do you think it was wrong and intrusive to require every male in a town to provide a DNA sample? The exercise identified the murderer, eventually.
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Old 30th December 2019, 03:24 AM   #44
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This case Colin Pitchfork
Not great video but..

https://www.youtube.com/watch?v=MhEAWPXqWn8
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Old 30th December 2019, 04:16 AM   #45
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Originally Posted by smartcooky View Post
I have a question for you.

Witnesses report that they see a black Chevy Suburban leaving the scene of a crime. Between all the witnesses, the Police manage to glean that the first letter of the licence plate was either "4" or "9". Black Chevy Suburbans are as common as mud, and this is a description that would match thousands of them.

Would it be appropriate, in your view, if the Police tracked down and interviewed every owner of every black Chevy Suburban in the area/city/state, or would you consider that to be a fishing expedition? Would that be imposing an undue burden on those who own black Chevy Suburbans?
That sounds like an impossible question to answer. To know whether it was appropriate, I would need to have some estimate of the risk that the partial number plate identification could be a false positive (meaning that lots of people could be investigated on spurious grounds), how intrusive the questioning is, the possible negative effects of being questioned, the probability of somebody who does in fact own a black Chevy being guilty (which depends on other factors used to narrow down and target the search), the likelihood of making an arrest as a result of the exercise. Depending on reasonable estimates of the answers, it could indeed be inappropriate and bad practice, or not.

Last edited by Elaedith; 30th December 2019 at 04:32 AM.
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Old 30th December 2019, 04:32 AM   #46
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Originally Posted by Rolfe View Post
And? I'm not sure what point you're trying to make there.

There was a case in England some time ago where every male in a particular geographical area was required to give a DNA sample in relation to a particular crime. The culprit persuaded a friend to trick the system and give his DNA instead. The friend later became suspicious of the fairy-story used to persuade him to carry out the trick and went to the police and confessed. DNA was then collected from the evasive party, no refusals accepted, no arguing, and he was found to be the murderer. So I think there are ways of dealing with people who refuse to co-operate.

Do you think it was wrong and intrusive to require every male in a town to provide a DNA sample? The exercise identified the murderer, eventually.
I don't believe they were 'required' to give a DNA sample - they were sent letters requesting a voluntary sample and had the right to refuse. Even then, there were civil liberties concerns raised at the time from what I've read, due to the social pressure to comply and the fear that refusal could mean being treated as probably guilty (as opposed to just not being eliminated as a suspect).
Police cannot take a DNA sample without consent in England and Wales unless the suspect has been arrested for a recordable offence (under PACE). I don't know exactly what rules applied at the time Pitchfork was arrested as I think that was before PACE. I assume the fact that he had substituted a DNA sample from somebody else would have been reasonable grounds for arrest and being treated as a suspect. However, if somebody could be arrested and forced to comply simply because they refused to provide a sample, that would seem to make a mockery of the term 'voluntary'.

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Old 30th December 2019, 06:39 AM   #47
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Inside the Cell The Dark Side of Forensic DNA, chapter 12

Originally Posted by Elaedith View Post
I thought it was more about privacy and the question of how many people might be needlessly investigated. I found this article which discusses (based on simulation) the possibility of more distant relatives being wrongly identified as first-degree relatives and some of the implications. One question is whether constraints should be placed on how far the follow-up investigations can go in terms of more distant relatives.
One of the coauthors, Professor Erin Murphy, wrote the book Inside the Cell The Dark Side of Forensic DNA. Chapter 12 covers familiar searches. The majority of the chapter deals with searches in law enforcement databases, but other databases are discussed.
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Old 30th December 2019, 06:56 AM   #48
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Originally Posted by Elaedith View Post
I don't believe they were 'required' to give a DNA sample - they were sent letters requesting a voluntary sample and had the right to refuse. Even then, there were civil liberties concerns raised at the time from what I've read, due to the social pressure to comply and the fear that refusal could mean being treated as probably guilty (as opposed to just not being eliminated as a suspect).
Police cannot take a DNA sample without consent in England and Wales unless the suspect has been arrested for a recordable offence (under PACE). I don't know exactly what rules applied at the time Pitchfork was arrested as I think that was before PACE. I assume the fact that he had substituted a DNA sample from somebody else would have been reasonable grounds for arrest and being treated as a suspect. However, if somebody could be arrested and forced to comply simply because they refused to provide a sample, that would seem to make a mockery of the term 'voluntary'.

My memory of this is hazy, I didn't even remember the man's name, but what on earth would anyone have thought they were achieving by such an exercise? If the murderer could simply "voluntarily" refuse to give a sample and that would be the end of it, why bother?
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Old 30th December 2019, 08:59 AM   #49
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Originally Posted by Rolfe View Post
My memory of this is hazy, I didn't even remember the man's name, but what on earth would anyone have thought they were achieving by such an exercise? If the murderer could simply "voluntarily" refuse to give a sample and that would be the end of it, why bother?
Actually I think the mass screening happened in 1986; later than I thought, so PACE would have been in effect. I was in Australia and a teenager at the time and don't remember hearing much about it, but I found a few articles online stating it was voluntary, like this one from the Guardian:
"Letters were sent to every male born between 1953 and 1970, who had lived or worked in the Narborough area in recent years, asking them to agree to give a blood sample"
"It was a voluntary scheme, and a few men declined, some saying they did not like needles, one or two saying they did not like police officers. But most of these men soon changed their minds."
"After eight months, 5,511 men had given blood samples and only one had refused"

As to 'why bother', I assume many people agree to provide a sample as it's an easy way to be eliminated, and further investigation would then inevitably come to focus on those who refused.
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Old 30th December 2019, 03:10 PM   #50
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That is one hell of a take-up for a "voluntary" scheme, so I think there's a wee bit more to it than is being revealed there.

But if indeed virtually 100% of a catchment of 5,512 people were happy to provide their DNA voluntarily based on nothing more than their age and their having had some connection with a particular town at a particular time, then I don't see that being a relative of someone who appears to be a relative of a perpetrator would trigger a significantly different response.

I note the reply to the question about the partial number plate identification was "it depends". Well fair enough, but if it is enshrined into law that more distant relatives of a relative of a perpetrator cannot even be asked to provide a voluntary DNA sample, this seems grossly excessive. Should we enshrine in law that nobody whose numberplate matches a partial match for a getaway vehicle should ever be investigated? Or indeed in the event of another Narborough situation, that it should be illegal to ask males from that area to provide a voluntary DNA sample? Because that in effect seems to be what you're asking for in relation to familial DNA matches.
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Old 30th December 2019, 03:22 PM   #51
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Originally Posted by Elaedith View Post
That sounds like an impossible question to answer. To know whether it was appropriate, I would need to have some estimate of the risk that the partial number plate identification could be a false positive (meaning that lots of people could be investigated on spurious grounds), how intrusive the questioning is, the possible negative effects of being questioned, the probability of somebody who does in fact own a black Chevy being guilty (which depends on other factors used to narrow down and target the search), the likelihood of making an arrest as a result of the exercise. Depending on reasonable estimates of the answers, it could indeed be inappropriate and bad practice, or not.
To me, this sounds like you are willing to shackle the Police because you fear that a few people might be inconvenienced with being questioned. I wonder if you would still feel that way if it was someone close to you who was murdered, then the case went cold, and years later, you found out that the Police had a valid lead that they never even followed.

I think you use the term "investigate" wrongly. If the Police follow up on vehicle identification, they are not trying to "investigate" every vehicle owner. What they are trying to do is eliminate that owner from their enquiries. If any vehicle owners want to be obstructive and don't wish to co-operate, that is their choice, but they should also be aware that doing so risks bringing an actual investigation of them, because the Police will rightly wonder if they have something to hide.

The same thinking applies to familial DNA, except that the DNA has already eliminated that person from being the perpetrator, because it is not a match. OK, so its possible that the familial testing might wrongly identify someone as a distant relative, but so what? Does that really matter? There are no jeopardy implications for a wrongly identified relative since they are not the person the Police are trying to find.

Sorry, but I'm not seeing any of the points you are bringing up as down sides of this investigative tool.
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Old 31st December 2019, 03:14 AM   #52
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Originally Posted by Samson View Post
Here is a practical question that an answer by one of the scientists on the thread would be helpful
1. Is there sufficient information in this court transcript to attempt a familial search?
2. If so do any privacy issues look obvious?

We would be looking for the owners of the male profiles that are not Mark Lundy. Ideally this would be edited, but I would not know which bits to cut. It is an important case.

Edited by Agatha:  Trimmed for rule 4. The original is freely available at http://injusticeanywhereforum.org/vi...c.php?p=187157
Thank you Agatha for the edit I dared not finesse so elegantly.
The issue with IA is it is not possible to post links to individual posts, so if anyone cares to address this vital issue that has totally confounded the knights and dames who comprise the New Zealand supreme court, the post is about half way down the page by me in Agatha's link dated

Tue Apr 18, 2017 3:10 am
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Old 31st December 2019, 06:14 AM   #53
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Originally Posted by Rolfe View Post
That is one hell of a take-up for a "voluntary" scheme, so I think there's a wee bit more to it than is being revealed there.

But if indeed virtually 100% of a catchment of 5,512 people were happy to provide their DNA voluntarily based on nothing more than their age and their having had some connection with a particular town at a particular time, then I don't see that being a relative of someone who appears to be a relative of a perpetrator would trigger a significantly different response.

I note the reply to the question about the partial number plate identification was "it depends". Well fair enough, but if it is enshrined into law that more distant relatives of a relative of a perpetrator cannot even be asked to provide a voluntary DNA sample, this seems grossly excessive. Should we enshrine in law that nobody whose numberplate matches a partial match for a getaway vehicle should ever be investigated? Or indeed in the event of another Narborough situation, that it should be illegal to ask males from that area to provide a voluntary DNA sample? Because that in effect seems to be what you're asking for in relation to familial DNA matches.
I haven't 'asked for' anything - I posted a link to a paper discussing some of these issues.

It was pointed out in the Guardian article that the degree of cooperation probably reflected the fact that this was a village where lots of people tend to know each other and feel a close connection to the incident, and that social pressure probably played a large role in the process. I'm not sure that being told you are a possible relative of somebody who may be a relative of somebody who committed a crime against somebody you have no connection with is quite the same. It's also potentially intrusive and disturbing, particularly if somebody finds out about people they didn't know were relatives, or didn't know they had a relative with a criminal conviction on an offender database.

It was also implied in the Rohlfs et al. paper that there is no way to reliably identify distant relatives from publicly available information, so that the actual process if identifying distant relatives would be intrusive and inefficient. It isn't a case of simply sending out polite letters to people asking them if they mind providing a sample.

There is also the issue of surreptitious collection of samples, which raises the issue of consent and surveillance. I'm not sure what the law is in the UK regarding this. There is a difference in my opinion between getting authorisation to collect a surreptitious DNA sample because there are strong grounds to suspect a specific person, and taking one because somebody might possibly be a relative of somebody who might be relative of an offender, and that is the easiest way to find out, especially if they won't cooperate with answering personal questions about their relationships with other people.

It was stated in the Guardian article that mass screenings are used much less often now as searches of offender databases are preferable. There was also change to the rules about keeping DNA samples permanently on the database, so that they now have to be destroyed eventually if there was no conviction for an offence. Frequent use of familial searching seems to go against both of changes in that it could lead indirectly to a return of mass screenings, and people who are not on the database because they have not been convicted of anything still end up being a drawn into an investigation through it. Potentially they would be better off had they been convicted and were on the database, because they could then be eliminated with no further intrusion.

I think all these factors need to be considered before deciding how familial searching should be used.

I'm not sure what you mean about banning number plate searchers. If a set of partial number plate matches is compiled based on publicly available information and those people are contacted, the process is targeting people it is meant to target, and without having accessed any information that was meant to be private. The paper is discussing the consequences of wrongly identifying people who were not meant to be targeted (because the relationship is too distant to be reliable) then proceeding to investigate them anyway, possibly by accessing many other sources of information that were not provided for that purpose. A closer analogy would be mistakenly identifying people who don't have a close enough match to the number plate to be targets, based on procedural inaccuracy, then deciding to do further intrusive investigation anyway, just to find out if they might be a match or not.

Last edited by Elaedith; 31st December 2019 at 06:16 AM.
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Old 31st December 2019, 07:03 AM   #54
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Originally Posted by Samson View Post
Thank you Agatha for the edit I dared not finesse so elegantly.
The issue with IA is it is not possible to post links to individual posts, so if anyone cares to address this vital issue that has totally confounded the knights and dames who comprise the New Zealand supreme court, the post is about half way down the page by me in Agatha's link dated

Tue Apr 18, 2017 3:10 am
Is this it?

http://injusticeanywhereforum.org/vi...188195#p188195
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Old 31st December 2019, 11:21 AM   #55
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Originally Posted by theprestige View Post
Yes, thank you
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Old 13th January 2020, 04:30 PM   #56
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Originally Posted by blutoski View Post
Two answers, because there were two points, one of which is more specific to your question. The context at the moment is volunteering your dna for personal entertainment, and finding it's been dragooned into a false positive match. In comparison, fingerprinting databases are the product of being arrested for a serious crime. This reduces the false positive rate considerably vs fingerprinting everybody in case they commit a crime later.

The second issue is the overlap problem when there's a mix of contributors. This never happens with fingerprinting. Prints are clearly individual, or if they're mixed, then you can't do a match. The danger is that with DNA, they're not able to get the same granularity as with fingerprinting, so the chances of false positives are several orders of magnitude larger.

IMO this would be a worst case scenario. For the same reason I object to universal mandatory drug screening. The false positive rate is too high, and experts have been disingenuously misrepresenting its reliability, which is SOP for quack pseudosciences. We had to review hundreds of cases in Canada last year when it was revealed the technicians misrepresented accuracy to the judge, essentially perjury, but the case is still in limbo.
Yep, my thinking is along similar lines. In the past few years, it's become increasingly apparent that a lot of "forensic science" is bunk and/or easily manipulated to aid the bias of investigators and prosecutors. Knowing that makes me really uncomfortable about the idea of law enforcement officials randomly trawling through DNA databases to look for suspects. When the news about using this technique to find the GSK first broke, something about it seemed "off" to me, and I still think it potentially opened the door for something ugly down the line. I just don't trust the law enforcement system as it currently exists in the US to not find a way to misuse this at some point, and it makes me a little nervous.

And that's not even mentioning that the indirectness of the process also gives me the heebie-jeebies. It's one thing for people to voluntarily provide support for a police investigation, but to inadvertently narc on your relatives when you thought you were doing something completely unrelated isn't something everyone would be comfortable with. Nor do I like the idea of the police investigating me (or anyone else for that matter) for no other reason than a suspicion about my DNA maybe being connected to a crime scene. One some level, I'm still probably heavily influenced by my training in social science research, which stressed the importance of ethics and informed consent; I know police work is very different, but I still get uncomfortable with the idea of people being thrust into criminal investigations without either their knowledge or consent, especially given how unethical criminal investigations can be. I want more transparency from the criminal justice system, not whatever this might open the door to.

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Old 15th January 2020, 07:49 AM   #57
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I've just finished reading a book about miscarriages of justice that has a lot to say about faulty forensics. The absolutely unscientific nature of hair and fibre analysis, ear prints, bite marks, shoe prints, footprints, and the serious flaws in fingerprint analysis. The only technique that actually survived rigorous double-blind testing was - DNA analysis.

I think you're in danger of letting the perfect become the enemy of the good. Yes there can be problems with DNA too, when people start over-interpreting low-copy-number traces, and ignoring the fact that DNA can be deposited in other ways than by being left by a criminal. These problems need to be identified and addressed, but we should not throw out the most promising forensic discipline there is because of identifiable and solvable problems.

When you have a full DNA profile from a rapist, recovered from semen in the vagina of the victim, do you really want to limit the ways by which the person who left that semen can be traced? If one of my relatives has done something like that, hell mend him and I wouldn't have the slightest bit of guilt if he was identified because I'd paid ancestry.com to analyse my DNA profile.

I don't see any difference between this and using a police database of DNA samples to identify a criminal. I go back to the case of Ronald Castree, who murdered Lesley Moleseed back in the 1970s. An innocent man spent 16 years in prison for that, before DNA testing was available. After he was exonerated another innocent man came under heavy suspicion, although the police decided not to charge him because they didn't want a repeat of the first miscarriage of justice. The case went dormant for years.

Then Ronald Castree got into some trouble with the police and had a DNA sample taken. It lit up like a Christmas tree against the profile from Lesley's murderer (the man had left a semen stain on her panties, although she had not been raped), which by this time was in the police computer system.

But they didn't immediately arrest Ronald Castree and charge him with Lesley's murder. They identified his whereabouts on the day it happened, looked at all the old evidence of cars and unidentified people who had been seen in the vicinity, and built the case against him that way. The DNA match gave them a suspect, and they were able to prove he'd done it by gathering other evidence.

I see no difference between doing this and checking public DNA databases for possible relatives of the murderer. It gives you a suspect, and then further investigation will show if that person is indeed in the frame. Yes there have been terrible miscarriages of justice due to faulty forensics and tunnel vision and indeed fraud. But I don't see why we should arbitrarily limit the use of the most reliable forensics technique that there is just from the fear that malpractice might happen, or because the idea makes some people irrationally uncomfortable (or some people would want to protect a relative who had committed rape or murder).
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Old 15th January 2020, 08:56 AM   #58
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Originally Posted by Rolfe View Post
But I don't see why we should arbitrarily limit the use of the most reliable forensics technique that there is just from the fear that malpractice might happen, or because the idea makes some people irrationally uncomfortable (or some people would want to protect a relative who had committed rape or murder).
Wow, way to misrepresent my arguments as badly as possible. But I guess I should have expected something so negative, misconstrued, and moralistic, given what I've seen of your post history. Nothing I said implies any of whatever strawman you seem to be trying to attack throughout your post.

Originally Posted by Rolfe View Post
I see no difference between doing this and checking public DNA databases for possible relatives of the murderer.
I do. And for reasons why, I'll point you back to blutoski's fingerprint analogy. It looks like we just see this differently. To be clear, I have no problem with the idea of using DNA to solve crimes, police databases, or even the police using public databases openly and ethically. My issue in this regard is mainly with the surreptitious use of people's genetic information for something they didn't consent to, and probably don't even consider because they aren't aware of the possibility.

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Old 15th January 2020, 09:51 AM   #59
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Originally Posted by Rolfe View Post
And? I'm not sure what point you're trying to make there.

There was a case in England some time ago where every male in a particular geographical area was required to give a DNA sample in relation to a particular crime. The culprit persuaded a friend to trick the system and give his DNA instead. The friend later became suspicious of the fairy-story used to persuade him to carry out the trick and went to the police and confessed. DNA was then collected from the evasive party, no refusals accepted, no arguing, and he was found to be the murderer. So I think there are ways of dealing with people who refuse to co-operate.

Do you think it was wrong and intrusive to require every male in a town to provide a DNA sample? The exercise identified the murderer, eventually.
Interestingly this was the first ever case in the world where DNA was used forensically to convict someone. It has some interesting details.

There were a series of rape murders, the details of the crimes led the police to think a single perpetrator was a serial rapist. The police managed to get a suspect who under questioning confessed for one rape, but the police wanted to convict him for the other rapes. There was semen left behind. At that time DNA testing had just been used in paternity testing so the police asked Nottingham University if they could do a similar test on the semen samples. Nottingham university did so and much to everyones surprise the man who confessed initially did not match. So the police informed the man's lawyer..

Then (again a world first) the police sampled (voluntarily) all men of an age that matched the suspect looking for a DNA match (5,000 in the end with only one refusal). As has been said the true guilty party got someone else to take the test, this subsequently came out and the correct person was convicted.
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Old 15th January 2020, 01:38 PM   #60
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Originally Posted by Planigale View Post
Interestingly this was the first ever case in the world where DNA was used forensically to convict someone. It has some interesting details.

There were a series of rape murders, the details of the crimes led the police to think a single perpetrator was a serial rapist. The police managed to get a suspect who under questioning confessed for one rape, but the police wanted to convict him for the other rapes. There was semen left behind. At that time DNA testing had just been used in paternity testing so the police asked Nottingham University if they could do a similar test on the semen samples. Nottingham university did so and much to everyones surprise the man who confessed initially did not match. So the police informed the man's lawyer..

Then (again a world first) the police sampled (voluntarily) all men of an age that matched the suspect looking for a DNA match (5,000 in the end with only one refusal). As has been said the true guilty party got someone else to take the test, this subsequently came out and the correct person was convicted.

I didn't know all these details. That's interesting.
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Old 15th January 2020, 01:50 PM   #61
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Originally Posted by ArchSas View Post
Wow, way to misrepresent my arguments as badly as possible. But I guess I should have expected something so negative, misconstrued, and moralistic, given what I've seen of your post history. Nothing I said implies any of whatever strawman you seem to be trying to attack throughout your post.

Still not seeing where I misconstrued your post. I don't agree with you, and I explained why. Does that warrant such a personal attack?

Originally Posted by ArchSas View Post
I do. And for reasons why, I'll point you back to blutoski's fingerprint analogy. It looks like we just see this differently. To be clear, I have no problem with the idea of using DNA to solve crimes, police databases, or even the police using public databases openly and ethically. My issue in this regard is mainly with the surreptitious use of people's genetic information for something they didn't consent to, and probably don't even consider because they aren't aware of the possibility.

Lots of personal information from people peripherally connected to a crime gets mixed in with the investigation of the crime. Vehicle registration numbers from cars seen in the vicinity are looked up and the owners traced and investigated. CCTV images of people in the vicinity are examined and the people may be traced and investigated. I don't see what's so sacrosanct about DNA.

If it did happen, or it seemed realistically likely to happen, that the use of this resource would cause a miscarriage of justice, and in particular that it would be more likely to cause a miscarriage of justice than all the shonky ear prints, fibre comparisons, bite impressions and so on that have been dreamed up over the years, yes it would be a bad idea.

But in contrast, it seems likely that this method of identifying a probable murderer or rapist is more reliable than all the rubbish methods that have been serially discredited over the years. Yes, we seem to disagree about this, but I can't see that vague squeamishness about the presumed sanctity of "people's genetic information" is a good reason for prohibiting the investigation.

If, in the case of the Lesley Moleseed murder, Castree had been identified because a sibling or a couple of cousins of his had used ancestry.com rather than through the police database, would you have regarded that as illegitimate and it would be preferable that the crime was never solved and Castree got away with it?
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Old 15th January 2020, 02:29 PM   #62
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Originally Posted by Rolfe View Post
Still not seeing where I misconstrued your post. I don't agree with you, and I explained why. Does that warrant such a personal attack?
When you completely ignore my actual arguments and reply to me with pearl-clutching strawman accusations about wanting to put arbitrary restrictions on things because I'm being irrational want to protect rapists, then yeah, I think it does. Especially considering that my temper for this place has been growing shorter lately given the usual quality of interaction here.

As for the only point you made that remotely addressed my actual arguments: I would think it would be obvious there's a difference between material connected to public activity (CCTC footage, license plates, etc,) and information people send off to a private company for a completely unrelated service. In public, there's no reasonable expectation of privacy. Seriously, there's no valid comparison there.

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Old 15th January 2020, 02:39 PM   #63
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If a police investigation isn't allowed to breach the privacy of citizens, it's not going to get very far in most cases.

Consider internet browsing history. People generally regard that as private. Should the police not be allowed to access this?
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Old 15th January 2020, 02:47 PM   #64
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Originally Posted by Rolfe View Post
If a police investigation isn't allowed to breach the privacy of citizens, it's not going to get very far in most cases.

Consider internet browsing history. People generally regard that as private. Should the police not be allowed to access this?
Not without permission or a warrant.

Laws against illegal searches and seizures exist, for good reason. A person's rights don't go out the window just because the police suspect them (or their relative) of a crime; and even if a person is guilty, the police don't get to do whatever they want to prove so.

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Old 15th January 2020, 02:53 PM   #65
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Originally Posted by Rolfe View Post
If one of my relatives has done something like that, hell mend him and I wouldn't have the slightest bit of guilt if he was identified because I'd paid ancestry.com to analyse my DNA profile.
I have a relative who is deep into government conspiracy theories and borderline freeman on the land. For example, he is big into buying and selling guns but won't get a dealers license because then the government could track his guns. So, he'd rather risk being caught illegally selling guns than allow the government to track his sales. (The fee is nominal compared to the volume he does.)

His adult kid got their DNA profile done on Ancestry and I think it was a bit for their own benefit and a bit of a middle finger to his paranoia. He hasn't been arrested, yet.
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Old 15th January 2020, 02:56 PM   #66
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Originally Posted by ArchSas View Post
Not without permission or a warrant.

Laws against illegal searches and seizures exist, for good reason. A person's rights don't go out the window just because the police suspect them (or their relative) of a crime; and even if a person is guilty, the police don't get to do whatever they want to prove so.
What if their spouse gives permission for the Police to search the house and the computer in particular when they drop by to ask?

Or what if they donate their computer without cleaning the hard drive, can the police buy it a goodwill and take a look?
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Old 15th January 2020, 03:04 PM   #67
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Originally Posted by Dr. Keith View Post
What if their spouse gives permission for the Police to search the house and the computer in particular when they drop by to ask?

Or what if they donate their computer without cleaning the hard drive, can the police buy it a goodwill and take a look?
If it's a shared computer, then yes. The spouse also has access. If it's a personal computer without shared access (ie, a laptop with a password), then no. For the second scenario: Yes, I guess? At that point, it's not that person's property anymore (similarly, I don't have a problem with cops testing discarded paper cups and the like for DNA).

AFAIK, at least, but I'm not a lawyer. It seems like you're asking for my opinion, but I don't really have one, and I'm not even sure why you're asking. TBH, it seems unnecessary, as these are now questions about property searches, and most jurisdictions already have guidelines for those situations.

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Old 15th January 2020, 04:22 PM   #68
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Originally Posted by Dr. Keith View Post
I have a relative who is deep into government conspiracy theories and borderline freeman on the land. For example, he is big into buying and selling guns but won't get a dealers license because then the government could track his guns. So, he'd rather risk being caught illegally selling guns than allow the government to track his sales. (The fee is nominal compared to the volume he does.)

His adult kid got their DNA profile done on Ancestry and I think it was a bit for their own benefit and a bit of a middle finger to his paranoia.
Good on the son/daughter for breaking the cycle of Stupid.

Originally Posted by Dr. Keith View Post
He hasn't been arrested, yet.
And he is not likely to be either. The Police aren't using familial DNA matches to trawl for petty felons - the expense doesn't merit the benefits.

For the record, I would be very happy for my familial DNA to help catch a relative who was a murderer or a rapist - another scumbag behind bars is a good thing.
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Old 15th January 2020, 04:34 PM   #69
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I think the process is only useful where DNA is deposited that can be virtually certain to have been left by the criminal, and of sufficient quality to give a profile that genealogical databases can work with. This is going to mean things like semen in association with a sex attack, or blood in association with a violent crime, are the main uses. I think it's a reach to imagine that police will try to get DNA from illegally-sold weapons, and then take that to a geneaolgical database to find the seller.

Given the history of police misuse of forensics, maybe there's something to be said for requiring a court order before being permitted to approach a genealogical database, with stipulations that the DNA available must be a complete profile of an identifiable individual, and that the circumstances of its recovery must be such that the DNA is overwhelmingly likely to belong to someone who has committed a serious crime. Then at least if the police started going on wild fishing expeditions there would be a way to rein them in. But I really don't think it should be forbidden.
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Old 15th January 2020, 08:36 PM   #70
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Foundationally valid?

Originally Posted by Rolfe View Post
I've just finished reading a book about miscarriages of justice that has a lot to say about faulty forensics. The absolutely unscientific nature of hair and fibre analysis, ear prints, bite marks, shoe prints, footprints, and the serious flaws in fingerprint analysis. The only technique that actually survived rigorous double-blind testing was - DNA analysis.
What book did you read? DNA from a single source is fine, but mixed DNA sampled, which are often recovered in forensic cases, have been analyzed subjectively in the past. See this link for a recent exoneration and discussion of mixed DNA analysis in light of PCAST. "In 2016, a presidential commission on forensic science citing Dror and Hampikian’s study found that human interpretation of DNA mixtures in crime laboratories was 'problematic' because of subjective bias, and it concluded that 'subjective analysis of complex DNA mixtures has not been established to be foundationally valid and is not a reliable method.'" The issue of whether or not mixed profiles that are analyzed via computer software are also subjective is a difficult one.
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Old 15th January 2020, 08:50 PM   #71
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Originally Posted by Rolfe View Post
There was a case in England some time ago where every male in a particular geographical area was required to give a DNA sample in relation to a particular crime. The culprit persuaded a friend to trick the system and give his DNA instead. The friend later became suspicious of the fairy-story used to persuade him to carry out the trick and went to the police and confessed. DNA was then collected from the evasive party, no refusals accepted, no arguing, and he was found to be the murderer. So I think there are ways of dealing with people who refuse to co-operate.

Do you think it was wrong and intrusive to require every male in a town to provide a DNA sample? The exercise identified the murderer, eventually.
Wow, really? What case was that?

My answer is that yes it is wrong and intrusive to require every male in a town to provide a DNA sample, even if such measures would identify a murderer. On the other hand, asking people to voluntarily submit DNA samples is another matter, and if you're lucky, maybe you don't find the perpetrator, but you find someone he's related to, and even just that could be an important clue. Then you can collect DNA samples without permission from door handles or a discarded coffee cup or something like that. No need to require anyone to provide samples if you can simply collect samples by following them around and seeing what they touch.

https://en.wikipedia.org/wiki/Golden_State_Killer

Quote:
Identification of DeAngelo had begun four months earlier when officials, led by detective Paul Holes, uploaded the killer's DNA profile from a Ventura County rape kit[152][153] to the personal genomics website GEDmatch.[154] The website identified 10 to 20 distant relatives of the Golden State Killer's (sharing the same great-great-great grandparents), from whom a team of five investigators working with genealogist Barbara Rae-Venter[155] constructed a large family tree. They identified two suspects in the case (one of whom was ruled out by a relative's DNA test), leaving DeAngelo the main suspect.[156] On April 18, a DNA sample was surreptitiously collected from the door handle of DeAngelo's car,[35] and later another sample was collected from a tissue found in DeAngelo's curbside garbage can.[157] Both were matched to samples associated with Golden State Killer crimes.[20]
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Old 16th January 2020, 05:44 AM   #72
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If you read further on in the thread, you'll find other people giving more and better details of that case.

Are you suggesting that accessing genealogical databases is unnecessary because the police should just follow everyone around and surreptitiously collect their DNA from discarded coffee cups and build up a database of everyone that way?
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Old 17th January 2020, 11:03 PM   #73
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I just wonder if the cost of genealogical databases should be subsidised by the government? They are using the database. Might as well say that police will have access to the data. Then no one who uses these services will have a right to complain. Then encourage its use. So the police would have DNA from a sizable % of the population.
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Old 18th January 2020, 01:28 AM   #74
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Originally Posted by ArchSas View Post
If it's a shared computer, then yes. The spouse also has access. If it's a personal computer without shared access (ie, a laptop with a password), then no. For the second scenario: Yes, I guess? At that point, it's not that person's property anymore (similarly, I don't have a problem with cops testing discarded paper cups and the like for DNA).

AFAIK, at least, but I'm not a lawyer. It seems like you're asking for my opinion, but I don't really have one, and I'm not even sure why you're asking. TBH, it seems unnecessary, as these are now questions about property searches, and most jurisdictions already have guidelines for those situations.
You seem bothered that the police may use my dna that I freely put out on the web to identify my father as a suspect in a crime. To me that is not unlike me allowing the police to search my home and shared computer without my fathers permission, even if my father is living with me.

I have rights. My father has rights. Where they conflict is the issue. My right to explore my heritage by publishing my dna will necessarily impact his right to privacy.
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Old 18th January 2020, 07:21 AM   #75
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I'm somewhat unclear whether people are objecting on the grounds that a relative who has actually committed a crime might be identified, or whether a relative (or even I suppose they themselves) might be falsely suspected. Another possibility I suppose is that a relative might suffer the minor inconvenience of being asked to provide a DNA sample to rule themselves out of consideration.

These are separate concerns, and I think need to be considered separately. If a relative of mine has actually committed a serious crime I do not think it is my job to shield them. I don't think, either, that the inconvenience of being asked to provide a sample to exclude them from suspicion should be something anyone ought to get their knickers in a twist about.

As regards false identifications, these are associated with mixed DNA and low-copy-number DNA and partial profiles. Law enforcement should categorically not be chasing up genealogical databases unless they have a high-quality full DNA from their suspect. Does this need to be legislated for? I'm not sure, because I'm not sure that it's even possible to interrogate a DNA database in any meaningful way unless you're starting with a complete, high-quality DNA sample from your suspect. But this is probably the issue that does need to be thought about. Basically, does the possibility of police going on fishing expeditions with a poor quality or mised sample have to be specifically prevented?

Other than that, I don't see the issue. Vague unease about "privacy" doesn't cut it for me. If I decide to put my own DNA on such a database I have decided that the privacy issue isn't a big deal for me. The remote possibility that a relative might be asked to provide a DNA sample to the police to rule them out of consideration for a serious crime isn't a big deal for me either.

It's hard enough to detect serious crime. Low-quality forensics have been the bugbear of investigations for many decades. DNA technology has the potential to overcome this. It's by far the best technology for identifying a suspect that there is. I do not think we should be tying the hands of investigators by prohibiting its use and potentially forcing them to fall back on ear prints or bite marks or shoe prints or fingerprints or hair comparison or fibre comnarison or any of the other dodgy methods that have led to the miscarriages of justice in the past.
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Old 18th January 2020, 08:01 AM   #76
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John Puckett case and partial profiles

Originally Posted by Rolfe View Post

As regards false identifications, these are associated with mixed DNA and low-copy-number DNA and partial profiles. Law enforcement should categorically not be chasing up genealogical databases unless they have a high-quality full DNA from their suspect. Does this need to be legislated for? I'm not sure, because I'm not sure that it's even possible to interrogate a DNA database in any meaningful way unless you're starting with a complete, high-quality DNA sample from your suspect. But this is probably the issue that does need to be thought about. Basically, does the possibility of police going on fishing expeditions with a poor quality or mised sample have to be specifically prevented?
Going on my memory of the John Puckett case (which may not be wholly accurate), but at one point in California you could search the database with a 7-locus profile, which is far from a complete profile.
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Old 18th January 2020, 11:22 AM   #77
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Originally Posted by Dr. Keith View Post
You seem bothered that the police may use my dna that I freely put out on the web to identify my father as a suspect in a crime. To me that is not unlike me allowing the police to search my home and shared computer without my fathers permission, even if my father is living with me.

I have rights. My father has rights. Where they conflict is the issue. My right to explore my heritage by publishing my dna will necessarily impact his right to privacy.
To some extent yes. And I disagree strongly. To me that example is completely unrelated (which I guess explains why your questions seems like non-sequitur to me; I genuinely had no idea what point you were trying to make, as my post hinted at), because someone's genetic information isn't something that can be searched (and I meant that word in the physical, literal sense of the word) in the same way as a physical object. They're just not the same thing, and I don't see that comparison as valid. Feel free to disagree, but that's where I'm dropping this because this probably isn't' going to go anywhere.

Originally Posted by Rolfe View Post
I'm somewhat unclear whether people are objecting on the grounds that a relative who has actually committed a crime might be identified, or whether a relative (or even I suppose they themselves) might be falsely suspected.
The latter, obviously. Seriously, you need to work on that problem of automatically projecting the worst possible intentions onto people who disagree with you. And while that might not seem worthy of concern for you, it is for me. It seems like what's contributing to the some of the difference of opinion is how one fundamentally understands the police. It seems like a lot of people here have an inherently positive view of law enforcement, and view it as a just institution that they can trust. That's not my default view.

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Old 18th January 2020, 11:22 AM   #78
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Mmm, perhaps my guess was out then. I do think there needs to be some account taken of the possibility of getting a false match from a partial profile.
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Old 18th January 2020, 11:25 AM   #79
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Originally Posted by ArchSas View Post
The latter, obviously. Seriously, you need to work on that problem of automatically projecting the worst possible intentions onto people who disagree with you. And while that might not seem worthy of concern for you, it is for me. It seems like what's contributing to the some of the difference of opinion is how one fundamentally understands the police. It seems like a lot of people here have an inherently positive view of law enforcement, and view it as a just institution that they can trust. That's not my default view.

I think you need to work on your problem of ascribing false motivations to factual posts, and of taking general comments personally.

I think I'm probably the last person on this forum to have any sort of rose-coloured glasses view of the police. That's precisely why I'm against barricading off a potentially fruitful method of finding the right person. As I said, attention needs to be paid to preventing fishing trips with partial profiles and low-copy-number DNA.
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Old 18th January 2020, 11:29 AM   #80
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Originally Posted by Rolfe View Post
I think you need to work on your problem of ascribing false motivations to factual posts, and of taking general comments personally.
Ok boomer.

But more seriously, everyone on this forum really needs to stop assuming their gut reactions and opinions are facts. You guys are ridiculous, it's like I'm back on 4chan sometimes.

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