Now I thought the only purpose of the above doctrine was to trick MBE test takers ("Multi-State Bar Exam" taken nationally in addition to State bar exams) into selecting the wrong answer choice in the minute and 48 seconds you have to answer each of 200 questions. Well Adam Liptak of the NY Times has a full story on this mainly American legal theory. The theory goes something like this: any unintended homicide during the commission of a felony, or immediate flight therefrom, is tantamount to murder. What the doctrine does is replace the specific intent needed to commit murder with the intent to commit a felony + an unintentional death (Burglary, Robbery, Arson, Kidnapping, Escape from police custody, Rape, and Sodomy) and finds that sufficient for murder. EG - if I decide to rob a house and the owner dies of a heart attack when he sees me: MURDER.
To take the theory one step further - since accomplices share in the intent to commit a felony, they "share" (for purposes of the law) the intent to commit murder if an unintentional death occurs. So it does not matter who pulls the trigger, it only matters that you wanted to commit a felony with your friends and someone died as a result.
Therefore you can have a result like the one in the NY times article where a man who lends his car so his friends can rob a safe owned by a local drug dealer, is found guilty of murder when one of his friends killed the drug dealer's 18 year old daughter. He is now serving life in prison without the possibility of parole. No doubt there are other less "sympathetic" examples, but why would the NY Times care to discuss those? For example, if I decide to help my friends burn down a house by pouring gas everywhere, and my friend physically lights the match, sets the house on fire, and somebody dies: not sure there is much of a difference between myself and my friend. But we are talking mass media here. You get side one on Tuesday and possibly side two Thursday. Sorry I digress.
The article states that felony murder originated as an English common law doctrine, but now America seems to be one of the few countries that still uses it (it would take about a month to verify). The justification seems to be if you share intent to commit a felony you should share in the results (seems arguable). It is sometimes argued that the doctrine has a deterrent effect, but I doubt those committing felony murder are up to date on legal jurisprudence.
I personally don't have much of a view on the issue as I'm not interested in criminal law, and policy ain't my thang. But I would nonetheless like to see the felony murder rule dropped so the damn MBE can stop tricking students.