I'm from the UK here. That would be manslaughter. Not murder. The whole concept of felony murder is insane and illogical. They went in to rob a place, and theft here would probably be like 5 years actual time behind bars. Here, the case would sit against the cop, and it would be weighed up to be self-defence, so no real charge. This dude, unless he had intention to kill, but simply was involved in the process of theft, then he really shouldn't be held responsible for other people's actions because he made a decision to go there. He's just a dumb kid who made a silly mistake. Basically taking their life away for a fuck up.

The part of the brain that processes risk isn't fully developed until like 24ish, so holding them accountable for something they cannot accurately make a decision on is weird punitive nonsense. Has it led to an actual decrease so is effective as a deterrent? Nah.