Cop out

when someone backs out from a responsibility or commitment because they're lazy or don't want to. The first simple definition that came to mind. To remember it, think of it this way: An angry Karen complains at the nearest police office(don't why but just for this ex.). The officer there named Jerry doesn't want to deal with that rn and leaves. He tells his trustworthy friend, officer Bob, "I'm out"...or in this case since he's a popo(slang for police), "COP OUT".