A bagman (or bag man), is a person designated to collect dirty money, e.g. in a protection racket. A bagman may also be known as a delivery boy or running man. Originally the term applied only to Mafia members collecting for mob bosses, but the term later spread to use in corrupt police precincts for patrolmen who picked up and delivered bribes from the local mob(s) to the precinct captain.
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The bagman may receive a fraction of the money collected. The term can also be used for a person who performs small tasks for the Mafia, such as chauffeuring or transporting goods.
The term is sometimes used in other contexts involving controversial money transactions.