> I wonder if his partner/friend got caught, and plea bargained to turn state's evidence against Marcus.

I always wonder a bit about how often these things end up like Rubin Carter, with the guilty party turning state's evidence against someone less guilty or entirely innocent. I mean... one presumes there's more evidence generated by being more involved with the crime, as in this case. If you catch whoever is most identifiable and turn them, there ought to be a lot of cases where you're starting with the worst player and cutting them a deal.