Gotham, Season 2

Jim Gordon:
I nearly crossed the line.

Captain Nathaniel Barnes:
The line? Let me tell you something about the line. My third tour, we're stationed in the desert. We captured three insurgents, when this sandstorm kicks up. Zero visibility. Then we start taking fire. We're getting lit up. Suddenly, I'm alone. I come across one of our prisoners. He's a kid. His hands are zip-tied. But he figures what the hell, he's gonna use the sandstorm to try to escape; so I jump him. And I take my gun and I jam it in his mouth. I figured it was just a threat; show him who's boss, you know? Next thing I know... I just pulled the trigger. Blew his head off. That kid woke me up every night for years. Until I made my peace with him. See, I come to find out I'm just a man. And at the right moment, a man might do anything. Any man. There is no line. There's just the law. That's what separates us from the animals.