in the hip pocket of (someone)

Under someone's control or influence, especially in an underhanded or unethical way, such as by bribery or extortion. It's pretty obvious that our national legislators are all in the hip pocket of corporations. You'll never get justice for it—half the police force is in the hip pocket of the mafia. A: "What exactly are you suggesting? That I'm in the hip pocket of the mob?" B: "Well, it just strikes me as odd that you're no longer going to testify against them."