Major Plothole (Spoiler!)
Actually this movie is ok to me, I just don't get why Danny should go through all troubles while in the end still he executed the two dirty cop by himself, it's true if you guys would say he went through the FBI to expose that two cop, but there's always chance of failure and still when you decide to shoot dead two cops whether they're dirty or not...be ready to face execution yourself, there's no way Danny could get away from it since Bubba the FBI guy already notice him and the motive. But if he by any chance decide to execute the both without anyone knowing anything, that way he might has his chance to get away with. I think it's better after all those troubles, he might just as well let FBI(or should it be Internal Affair) do the job.
Anyway, assuming your wife's killer by just a single piece of 'red' hair is totally ridiculous. Let's just say that he is right eventually, but it makes him looks like Sherlock who were made just to fit in the plot.
So guys, are we on the same boat or you guys do have defense about those?