He didn't need to shoot to kill. Karen probably wouldn't think twice about it except that she knows John usually doesn't on purpose. This whole situation isn't exactly usual, though. She's not usually in the middle of shootouts. Their targets aren't usually people who abuse their wives and leave them nearly dead in the hospital. She knows about John's history, what happened to his ex and how hard that was on him. It's why at least a part of her expected this tonight. As long as Brady was alive, his wife would have stayed with him or had to spend the rest of her life looking over her shoulder. Either way, it wouldn't have ended well. It shouldn't be, but this is the neatest solution, especially after he'd come running out of the dark, brandishing a weapon.

Sometimes there just aren't other options. She hates that, but she knows it.

"Good," she says with a nod of her own. "We should ditch that gun, too. Use it again, it could be traced back to this." She knows he knows all of this. He's the goddamn homicide detective. It helps a little, though, to talk it through, to have a plan, to approach this as rationally as possible. What happened here tonight is something she can't bring herself to regret, but they still need to be smart about it.