get away with

1.  Escape the consequences or blame for, as in Bill often cheats on exams but usually gets away with it. [Late 1800s]
2.  get away with murder. Escape the consequences of killing someone; also, do anything one wishes. For example, If the jury doesn't convict him, he'll have gotten away with murder, or He talks all day on the phone--the supervisor is letting him get away with murder. [First half of 1900s]