Originally Posted by
halides1
From ABC, "'Sirens from the police cars in the parade may have drowned out the sound of the approaching train,' Vatankhah said." and "Patricia Howle was sitting traffic with her daughter watching the parade go by when she heard the train honking its horn." and "A Union Pacific spokesman Tom Lange said it appeared safety devices at the crash site were working. But there were conflicting reports by eyewitnesses about whether the gates went down at the crossing when the train approached."
The gates were almost undoubtedly down. People tend to have little recollection of time sequences when terror strikes.
Union Pacific's locomotive fleet (except some yard goats) all have video event recorders triggered by horn and brake application. The NTSB will be able to sort this out.