He knocks her ass out, and this whole time he's telling the story to Darren like he was explaining to her in very measured tones and she was being obstinate and screaming, which doesn't really seem to be true. He just kind of karate-chopped her and she dropped.
Darren: "Also, if you're so reasonable then how come the Killing took three different murders? And why did you just pull out my gun, that you found a couple episodes ago?"
Jamie: "Okay, that's a good question. The first time I killed her, it was just the karate chop at the Casino. And then the next time, she woke up in my car so I chased her through the woods. That part sucked for both of us!"
Darren: "I bet. It gets cold here because of the shitty weather."
Jamie: "So then the third time I killed her, it was for gay love."
Jamie: "Yeah, for real."
Darren: "I have to go."
Jamie: "Not if I shoot you first! You are very ungrateful about all this."
Darren: "I kind of ended up in a wheelchair because of this, though."
Jamie: "I think it was more that you are a jerk! You cheated on Gwen with choking whores! That is very rude! And I think you also let your wife die, to become famous!"
Darren: "Now you just sound crazy."
Jamie: "THIS IS THE GAME OF THRONES! WE WILL TAKE OVER AMERICA!"
Linden: "Mr. Wright, please put down that gun. Shooting Darren at this point would be obnoxious."
Jamie: "I am in a kind of mental Viet Nam right now. I have no exit strategy."
Darren: "Jamie, shooting me is literally the only way you could make this worse."
Jamie: "Mr. Mayor! We can still do this!"
Darren: "Oh girl."
He goes to shoot Linden, but Holder shoots him instead, and then it's just Holder shaking and Gwen crying and Sarah -- admittedly, it's her first response which is lovely -- awkwardly patting her.
Linden: "Human. We are alive, Human. Your emotions are realistic."
Gwen: "I know but that was just really effed up! Also, what the hell is going to happen for the rest of this episode?"
Holder: "I just killed the cutest little guy. I need hugs too."
Darren: "I do not believe that anybody will ever love me more than Jamie Wright. It is a complicated issue. And also, how is this going to affect my mayoral campaign? It would be very ironic if Jamie accidentally caused the deaths of like ten people and two seasons of a TV show and then I lost because of him. In fact, it would kind of prove his point. And, too, is what he said true? Do I unconsciously let other people do my dirty work? I just thought I was selfish because that's how grieving works. But if poor Jamie was right, I might need therapy."