The final police report on the Oct. 1 Las Vegas shooting has been released. Authorities were unable to determine the gunman's motive for the attack. Sheriff Joe Lombardo said Stephen Paddock showed evidence of a “diminished mental state” in recent years. He said Paddock had not been diagnosed with or treated for mental illness. An examination of Paddock's brain at Stanford University found no major abnormalities. The FBI is expected to release a detailed review by the end of the year.