detective (n.)
- asker
- bailiff
- beadle
- beagle
- captain
- catechist
- commissioner
- constable
- cop
- copper
- cross-questioner
- deputy
- dick
- examiner
- eye
- fed
- federal
- gendarme
- gumshoe
- hawkshaw
- inquirer
- inquisitor
- inspector
- interlocutor
- interrogator
- interviewer
- investigator
- lieutenant
- marshal
- narc
- officer
- operative
- patrolman
- peeper
- plainclothesman
- policeman
- policewoman
- pollster
- querier
- questioner
- quizzer
- reeve
- revenuer
- roundsman
- sampler
- sergeant
- sheriff
- sleuth
- snoop
- snooper
- superintendent
- tec
- tipstaff
- trooper
