call sb's bluff

call sb's bluff (challenge someone to substantiate their claims, to show that they are not being deceptive and can actually do what they say they can do ) — вывести на чистую воду (разоблачить обман, заставив раскрыть карты); не поддаться на провокацию; не дать взять себя на пушку

Example 1: My girlfriend always said that she didn't want to get married so I called her bluff and asked her to marry me. She said yes.

Example 2: She called his bluff and dared him to tell everyone what he knew about her.

Example 3: And you can trap a man who boasts. You can call his bluff. (Gr.Green, “The Comedians”) - Хвастуна легко заманить в ловушку. Заставить его открыть карты.

In poker-playing a bluff is a display of confidence (perhaps from a Dutch word for boast) such as heavy betting on one's own weak hand to deceive opponents and cause them to throw up their own stronger hands and lose their stakes. To 'call' such a bluff is to remain in play and require the bluffer finally to show what cards are held; a call is simply a demand that a player reveal his hand because his bet has been equalled.

уличить во лжи
[вывести на чистую воду]