what did he do wrong?
should be considered inoperable if its a parts kit, even if he has the reciever but while its dissasembled, it shouldnt be considered an "Assault Rifle"
any light on what this man did wrong?
"He had all the parts to make a tactical assault AR-47 Glock, which would've compelled him to buy a high capacity bullet clip for it, take it to the nearest populated area, and mow down scores of people. They averted another holocaust by takin his gun away. He might've also bought a high caliber sniper rifle or a high explosive grenade bazooka."
He was a felon with a gun. That's what he got the time for. The attempted ownership of an assault weapon was an additional charge. If he had California compliant parts in his box it probably would have been a lesser charge but a charge nonetheless. The main charge was for his other gun that was complete.