In the worst mass shooting by a lone gunman in US history, on August 3, 2018, Clark County Sheriff Joe Lombardo held a press conference on the release of the
LVMPD Criminal Investigative Report of the October 1 Mass Casualty Shooting.
He said the 10-month investigation had revealed no evidence of conspiracy or a second gunman, and that the
gunman's motive had not been definitely determined. Lombardo said "What we have been able to answer are the questions of who, what, when, where and how...
what we have not been able to definitively answer is why Stephen Paddock committed this act."
[111] A report published by the FBI's
Behavioral Analysis Unit in January 2019 said that "there was
no single or clear motivating factor" for the shooting.
[112]
Paddock's only recorded interactions with law enforcement were
traffic citations.
[11]