NBC News' Chris Jansing has the latest details in the investigation into why suspected Las Vegas shooter Stephen Paddock carried out the largest massacre in U.S. history.Oct. 3, 2017
UP NEXT
'Schools have had enough': Universities respond to student protests
09:33
Kennedy family members endorse President Biden
03:37
Stepson of former ‘Real Housewives’ star arrested on Jan. 6 charges
00:51
Doris Kearns Goodwin on watching JFK grow as a candidate and leader
08:48
'I will not have any jurors intimidated': Judge issues warning during trial
12:39
Doris Kearns Goodwin re-lived the 60s with her husband for 'An Unfinished Love Story'