Originally Posted by JTF
Regarding point 1, I have demonstrated with citations from the forensic literature that the substance was not bleach, nor was it a bleach-cleaned bloodstain. You have been told this repeatedly, and your response is to offer an insult instead of an explanation. And this was after you were called out for exaggerating the strength of the luminol reaction. Can you cite forensic evidence demonstrating that bleach and paint thinner were used? If you cannot, then it isn't worth discussing.
Regarding point three, The National Research Council's 2008 report Ballistic Imaging
stated, “A significant amount of research would be needed to scientifically determine the degree to which firearms-related toolmarks are unique or even to quantitatively characterize the probability of uniqueness.”
The 2009 NAS Report “Strengthening Forensic Science: A Path Forward” concluded in part, “Toolmark and firearms analysis suffers from the same limitations discussed above for impression evidence. Because not enough is known about the variabilities among individual tools and guns, we are not able to specify how many points of similarity are necessary for a given level of confidence in the result. Sufficient studies have not been done to understand the reliability and repeatability of the methods.”
In 2011 Paul Giannelli wrote, "In a different passage, the [NAS] report remarked that “[m]uch forensic evidence ‘including, for example, bite marks and firearm and toolmark identifica- tions’ is introduced in criminal trials without any meaningful scientific validation, determination of error rates, or reliability testing to explain the lim- its of the discipline.” (Id. at 107-08.)"
In 2017 Sarah L. Cooper wrote, “However, overall, Strengthening concluded that ‘The scientific knowledge base for tool mark and firearms analysis is fairly limited.’” She went on to say, “The NAS [National Academy of Sciences] commented that ‘[t]his AFTE [association of firearms and tookmark examiners] document, which is the best guidance available for the field of tool mark identification, does not even consider, let alone address questions regarding variability, repeatability, or the number of correlations needed to achieve a given degree of confidence.’”
Thus Mr. Newhouse's claim of uniqueness is unscientific. Maybe someday the pro-guilt commenters will stop offering up rose fertilizer while claiming that it smells like roses.