throw someone under the bus

throw someone under the bus
 v. phr.— «We have benefited from having him here and I don’t feel any need to throw him under the bus.…He’s gotten pretty good results. He could use some help from his members, who could pay more. He has had some rough times, but you have to look forward.» —“Director Of Bureau Under Fire” by James Lawless Plain Dealer (Cleveland, Ohio) Feb. 20, 1995. (source: Double-Tongued Dictionary)