aid and abet

verb3

1. •
   To assist (someone) in an illegal act as an accessory or accomplice.

   • A bank employee was accused of aiding and abetting the gang of robbers.
2. •
   To assist someone in (an illegal act) as an accessory or accomplice.

   • Murder itself was not more sternly and certainly punished in the State of Maryland, than that of aiding and abetting the escape of a slave. — 1881
3. •
   To be an accessory or accomplice to someone in an illegal act.