The husband could not be convicted of felony murder in this case because there was no murder, which is an UNLAWFUL killing.
The wife's killing of her attacker was lawful because she was acting in self defense. Accordingly, there was no murder, and the husband cannot be convicted of felony murder. Or at least I think that's how it works.
Can he be charged (in some way) with the death of the intruder, since he set the plot in motion?
The felony murder statute here includes any death caused by the underlying felony, regardless of the status of the homicide. It's the felony that makes it a murder, it doesn't have to be a murder under any other definition.
As I understand the law a criminal can be charged with murder for the death of one of their accomplices during the commission of a crime even if they didn't do it themselves.
For example, Say two guys try to rob a bank. The security gaurd shoots and kills one of them while the other gets away in the car. When caught later the one who ran can be charged with murder because it would not have happened had he not committed the crime.
Any lawyers out there who can explain it better?