Geary Danley is an American who on October 1, 2017, was misidentified as the perpetrator of the Mandalay Bay Resort Shooting (October 1, 2017) by users on 4chan in the politically incorrect thread.
The users named Geary Danley as the shooter who opened fire claiming that Danley was a far Left wing loon', a Social democrat, and was anti-Donald Trump, based on his likes and interest in his Facebook profile. 
The comments were picked up by several blogs and news sites, including an article by the Right wing political website, the Gateway Pundit. The false news was also incorrectly posted by an anonymous editor on Everipedia but was quickly corrected by other community members to clear Geary Danley's name from any allegations.  Eventually the real perpetrator was identified as Stephen Craig Paddock, a companion of his former wife Marilou Danley, whom he divorced in 2014.