throw (oneself) on/at the mercy of (someone)
To plead with someone, especially a figure of authority, to show one lenience and mercy. I have no excuse for what I did. I can only throw myself on the mercy of the duke and beg for his forgiveness. She threw herself at the mercy of the court, saying that her dependence on drugs led her to commit those crimes.
throw oneself on the mercy of
some authority Go to throw oneself at the mercy of some authority.