cut off at the pass

To keep one from doing something (that usually involves an escape). Jeremy has been acting suspicious, so he's probably going to try to sneak out tonight, but I'm going to cut him off at the pass.

Fig. to block someone's effort to get away; to thwart someone's efforts. They are ahead now, but we'll cut them off at the pass. Try to cut off the bandits at the pass!

To stop or intercept. This expression comes from chase sequences in western movies of the 1930s and 1940s, in which pursuers (usually the “good” cowboys) would try to intercept their quarry (the outlaws) at a mountain pass. It gradually was extended to other endeavors. According to Brewer’s Dictionary of Twentieth-Century Phrase and Fable, in 1973 President Richard Nixon used the term on the Watergate tapes, saying that the charge of obstructing justice might be cut off at the pass.