I'm still researching this all but I discovered a forgotten shooting that happened the same year as Sandy Hook (2012).The Clackamas shooting was done on Dec 11th, just says before the Sandy Hook shooting which happened on Dec 14th.
The shooter (Jacob Tyler Roberts) allegedly went through a breakup/rejection where shamed he would tell his friends he was "Giving away all his 'stuff' and moving to Hawaii". Soon after he'd visit one of his friends where they would smoke weed and talk, leading Jacob to steal his friends AR-15 and legally buy the ammo.
On Dec 11th wearing a black sweater, black pants, boots, and a "expressionless mask", Jacob Roberts entered into the Clackamas Town Center, to the food court, and opened fire. Witnesses claim before the shooting they assumed the suspect (Jacob Tyler Roberts) was dressed for a prank and or came from a "Paintball game" which they couldn't be more wrong. During the shooting his AR-15 would jam prompting him to end the shooting earlier then probably expected by him leading him to deviate from the shoppers and enter a employees only corridor, to a lower level where he would kill himself.
This isn't the full story but I thought I'd get this out here.[You must be registered and logged in to see this image.]
CCTV footage of Jacob Roberts during the shooting.
"Me And You Are Living Forever, Until We Don't."