I have been thinking about this for several weeks now but it's starting to look more and more feasible. Could it be that Joe Carroll's motive is to turn Ryan into a serial killer? What is Ryan's body count right now? It's gotta be a dozen or so. Futhermore, Joe has shown he doesn't give a flip about his followers. He keeps throwing them out there like pawns for Ryan to pop off. When Vince was on the ground reaching for the gun, I am thinking "just shoot him in the shoulder". Nope. Kill shot.
Which brings me to my next point: when any law enforcement officer takes a life in the line of duty, it is protocol to put him on "administrative leave" or a desk job until a proper investigation of the incident can be performed. Yet, here is knocking folks off left & right like he is shooting free throws. And he is not even a full FBI agent! He is some kind of unofficial consultant.