A 20-year-old’s perplexing place in the catalogue of American gunmen The Washington PostThomas Matthew Crooks: What we know about Donald Trump’s attacker BBC.comAfter Some Trial and Error, FBI Cracks Trump Shooter’s Samsung Phone PCMagTrump Shooter Crooks Wasn’t on Rifle Team or Bullied, According to School The Daily BeastTracing the Trump Gunman’s Final Months and Days The Wall Street Journal