Even before the final vote was tallied, Democratic officials were finalizing ambitious plans for rallies, voter registration drives ... coming together that allowed 20-year-old Michael Thomas Crooks ...

Thomas Crooks was talking to imaginary people, dancing alone in his room and even researched the distance for the assassination of President John F. Kennedy before attempting to kill President Trum… ...

Thomas Crooks was a nerdy engineering student on the dean’s list. He stockpiled explosive materials for months before his attack on Donald Trump, as his mental health eroded.

Emails and essays obtained by CBS News shed new light on Thomas Matthew Crooks, the 20-year-old who opened fire at a Trump rally in Butler, Pennsylvania.

Via New York Post -- Almost nine months ago, a seemingly mild-mannered college student named Thomas Crooks shocked the world when he attempted to assassinate Donald Trump at a rally in Butler ...

Voter records in Allegheny County show Crooks is a registered Republican voter. However, according to federal campaign finance records, Crooks appears to have donated $15 to the Progressive ...

It's unlikely that the parents of would-be Trump assassin Thomas Crooks will face charges, experts say, especially given Crooks' adult age and legal gun ownership.

Minutes after Thomas Crooks came within an inch of killing Donald Trump, it was already clear what would happen next, and in the subsequent days a number of conspiracy theories indeed emerged ...

Thomas Matthew Crooks' cause of death was a gunshot wound to the head, according to the Butler County Coroner's Office. His manner of death was ruled a homicide.

Thomas Matthew Crooks worked for BlackRock "in the past" and BlackRock owned the building Crooks stood on when he shot at the Trump campaign rally.

Thomas Crooks was a brainy and quiet young man who built computers and won honors at school, impressing his teachers. Then he became a would-be assassin.

Questions remain over what the motive was for 20-year-old Thomas Matthew Crooks to target former President Trump, but this is what initial investigations and reporting has revealed.