be hoist/hoisted by/with your own petard
hoist by/with (one's) own petard
Injured, ruined, or defeated by one's own action, device, or plot that was intended to harm another; having fallen victim to one's own trap or schemes. ("Hoist" in this instance is the past participle of the archaic verb "hoise," meaning to be raised or lifted up. A "petard" was a bell-shaped explosive used to breach walls, doors, and so on.) I tried to get my boss fired by planting drugs on him, but I was hoist by my own petard when the police caught me with them beforehand. The senator continually called on authorities to investigate her political opponent's alleged tax evasion. Now it seems as though she may end her political career hoist with her own petard, as federal agents indicted her for tax fraud on Monday.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
be hoist/hoisted by/with your own peˈtard(British English) be caught in the trap that you were preparing for another personThis is from Shakespeare’s play Hamlet. A petard was a small bomb.
Farlex Partner Idioms Dictionary © Farlex 2017