Meaning of set a thief to catch a thief | Babel Free

Definitions

To employ an unscrupulous person in order to catch another unscrupulous person.

Examples

“The morality of setting a thief to catch a thief passes muster in the English force; but they do these things better in America. Pinkerton's system for the detective police in America is vastly superior to the British system.”

CEFR level