WHAT WE KNOW ONE YEAR LATER----THOMAS CROOKS, THE ASSASSINATION ATTEMPT ON PRESIDENT TRUMP

One year after Thomas Crooks tried to kill President Trump, here's what's known about him

One year ago on Sunday, Thomas Crooks tried to assassinate President Trump at a campaign rally in Butler, Pennsylvania. A CBS News investigation shows what is known about Crooks. CBS News' Scott MacFarlane reports. MORE AT One year after Thomas Crooks tried to kill President Trump, here's what's known about him | Watch