24 Season 3 and the Duty to Rescue [spoiler alert for those who haven't seen the season yet]:

I'm rather behind the times, but I just finished watching season 3 of "24." As you may recall, when Alan Milliken is dying of a heart attack, his wife Julia is about to give him his heart pills when the president's ex-wife Sherry persuades her not to. Alan, being handicapped, can't get to the pills himself, and dies.

For the rest of the season, Julia and Sherry worry that they are going to be convicted of murder. My question is whether such a charge would stick under California law for either or both. There is generally no duty to rescue, but as Alan's wife, did Julia have some legal obligation, enforceable by criminal law, to come to his aid? And while I presume Sherry had no legal obligation whatsoever to Alan, did she somehow violate the law by persuading Julia not to give him the pills?

UPDATE: The standard answer in criminal law is that a spouse does have a duty to rescue, enforceable by criminal law. That leaves the question of Sherry's liability. What exactly would she be guilty of?