That's because you came down here and warned him.
5 seconds sound clip from the The Westerner (1940) movie soundboard.
You can hear this line at 00:48:30 in the DVD version of the movie.
Quote context
[...]
- They're outside right now, a whole wagonload of them.
- A wagonload? Why, I can handle a train load of them. I'll tear their livers out.
- It'll be Roy Bean. Where is he?
- That's because you came down here and warned him.
- Make a move and I'll kill you.
- Cole, start collecting them shotguns.
- Uncork them rifles now and set them down this end of the bar, easy-like. Go on.
- Now, I'll take yours, Judge.
[...]