Prison guard
A prison guard, corrections officer, or jailor was a guard officer responsible for supervising inmates who were being held in custody of the law, under the command of a warden. The term "screw" was slang term for a prison guard. 

According to a former inmate, half the screws on Tellun were said to be Andorians. ()

After Tom Paris and Harry Kim discovered themselves in Akritirian maximum security detention facility, Kim was surprised to learn that it was "a prison without guards." Paris then explained that "The other inmates say this place is three hundred meters . Maybe the Akritirians figure guards aren't necessary." ()

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Legal occupations