put the finger on (one)
To identify and accuse one of doing something; to inform on one to an authority figure. Don't you dare put the finger on me! I had nothing to do with the deal going sour. I fear my life is in danger now that I've put the finger on the mob boss.
put the finger on someone
and lay the finger on someoneSl. to accuse someone; to identify someone as the one who did something. Tom put the finger on John, and John is really mad. He'd better not lay the finger on me. I didn't do it.
put the finger on
Inform on, as in The witness put the finger on the defendant. [Slang; c. 1920] Also see put one's finger on.
put the finger on
inform against someone to the authorities. informal put the finger on
Slang To inform on: The witness put the finger on the killer.