The guy had a public defender, ergo he couldn't afford a good attorney, which certainly must have factored into the equation. If I had been one of the attorneys, I would have tried to terminate my relationship with the real culprit in a way that would allow me to talk. If that was not an option, I'd probably keep quiet, keep my license and not sleep well for a while. Luckily, I intend to stay clear of the criminal justice system and thereby avoid getting caught in a similar dilemma.
On a side note, in business if your client tells you about his intent to cheat or illegally exploit the other party of his contract, you as an attorney have to act upon that information. If your client is a criminal, however, you must keep everything confidential unless your silence will cause "imminent bodily harm". Now, which seems to be valued more in the system, money or lives?