So it seems to mean being involved in another felony, in which a murder also occurred?
---"being involved in", as in "commission of a felonious act",
such as robbery, arson, rape, etc;
---"in which a murder" occurred--no. In which a death
occurred, which was a (unintended) result of the felonious
act.
Joe Felon robs a bank (intentional felonious act). Marvin
Milquetoast watches Joe from back of lobby, has anxiety
attack and dies from heart failure.
Joe Felon intended to rob (a felony crime). He didn't
intend to give Marvin a fatal heart attack, but it happened
as a result of Joe's felonious act. If Joe hadn't robbed the
bank, Marvin would (presumably) still be kicking.
Another example: Joe drives at high speed from bank
robbery. As he runs a red light, a mom driving a minivan
on cross street veers and brakes, and impacts another
vehicle. Any fatalities in the collision could be charged
as felony murders, by Joe.
Somebody suggested a requirement for "two or more"
criminal actors, for charging felony murder. Don't see
any reason for that, unless it's a quirk in the way specific
state writes the statute.