James Holmes bought his last gun — an AR-15 assault rifle — on June 7, 2012.
In the two months prior, the then 24-year-old also legally purchased a Remington 12-gauge shotgun, two .40-caliber Glock handguns, tear gas grenades, bomb-making material, handcuffs and more than 6,300 rounds of ammunition.
The night Holmes attacked the Century 16 movie theater in Aurora, Colo., he was wearing a bulletproof vest and leggings, a gas mask, a ballistics helmet and gloves. Roughly 30 minutes into the movie, Holmes released the tear gas he had bought online, causing the unsuspecting attendees to cough and choke as their eyes burned. Then the shots came. Twelve died and 70 others were injured that night in July 2012, in what was then said to be the highest-casualty shooting in U.S. history.
