throw under the bus

verb2

1. •
   To betray or blame (something or someone); to deliberately put (something or someone) in an unfavorable situation and then leave to their fate; to make (something or someone) into a scapegoat or otherwise abandon for personal gain.

   • "A person who does things for me and befriended me and helped me out when I needed help, I'm certainly not going to throw them under the bus," she said. — 1993
2. •
   To discard or disown.

   • A recent magazine article discussed the need to throw under the bus worn-out cultural catchphrases, with the first being “throw under the bus.” — 2008