I believe Angeleos' charge was Felony Murder and not First Degree Murder. Big difference, Felony murder could mean he was there as a passive accomplice. Does not mean he had to commit any act of deadly violence, just be a party of it.
Two guys break into a house, (commission of a Felony) the homeowner shoots and kills one of the bad guys. The other bad guy can be charged with Felony murder because a death occurred during the commission of a Felony. Some you are robbing with a squirt gun has a heart attack and dies you could be charged with Felony Murder.
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