Season 2, Episode 10
A traveling circus and a Pinkerton detective visit Four Corners and with their arrival comes the killing of a local woman. Josiah had been visiting a neighboring town when a previous murder had been committed and is now suspected. His being secretive of that visit doesn't help the situation.
Buck: You bet against me?
Ezra: It's a matter of principle now.
JD: Principle? Since when do you two have principles?