[Note: this blog is part of a research project. It is not especially aimed at a broad public. It’s a place for the author to keep notes, and it is made public in case others find it useful or interesting. Please do not quote.] 

Daniel Penny pretty obviously choked Jordan Neely to death — even though Penny’s attorneys cite a number of other factors, including Neely’s drug use, as more likely causes. When you’re caught on video choking someone, who then dies, it certainly looks like killing is a foregone conclusion.

An amateur’s reading of the situation is that Penny might well have been justified in trying to subdue Neely, who was being disruptive and aggressive on a subway train. (Was he dangerously aggressive? I don’t know.)

There is of course a pretty clear line between subduing and killing. Penny may well be part of a substantial history of vigilantes who tried to do the right thing, but ended up overdoing it — and hence, doing the wrong thing. That’s one key criticism, whenever civilians take law enforcement into their own hands: they’re not going to do it well, in particular with regard to drawing the line between justified and unjustified force.

But then again, police don’t always recognize that line either.