Seeing that his accomplice died as a result of the crime, he should also be charged with murder.
That is the Felony Murder Rule . Commit a felony, someone (ANYONE) dies in the commission of it, and you're on the hook. The classic example is a getaway driver (who never enters the store) who is charged with murder when the shopkeep fires at the gunman and accidentally kills a customer. Driver never went inside, because they didn't want to get in trouble... and still get a murder pinned to them.