slap (one) on the wrist
To issue or administer a very mild, often inconsequential punishment or warning to one. The CEO ripped off millions of people, and instead of throwing him in jail where he belongs, they're just slapping him on the wrist. Of course the country is going to keep developing nuclear weapons if all we do is slap them on the wrist for it.
Farlex Dictionary of Idioms. © 2024 Farlex, Inc, all rights reserved.