on somebody's head be it
on (one's) (own) head be it
The blame, consequences, or responsibility of a risky, dangerous, or foolish decision or action belongs to someone and no one else. If she wants to quit a high-paying job to chase after some fantasy of being a travel writer, then on her head be it.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
on somebody’s (own) head ˈbe it(often used for warning somebody) somebody is alone responsible for the results of their action or decision: You refuse to go to your own daughter’s wedding? On your head be it! ♢ On his own head be it if he decides to leave college early.
Farlex Partner Idioms Dictionary © Farlex 2017