In the novel Chigurh allows himself to be arrested…
Before Chigurh executes Carson Wells he is humoring himself by lecturing Wells on his personal philosophies, similar to the film but one of the tidbits shared with Wells that is not included in the film is that Chigurh voluntarily allows that deputy to arrest him (the opening scene in the film) just to see if he can free himself of being handcuffed and arrested, by “an act of sheer will.”
I love these little details in the novel, as they expand on the mindsets/motivations of already intriguing characters.