| plainclothes officer(noun, expression, agent, spy, police) |
| pointer |
| police officer(noun, expression, agent, spy, informer) |
| preserver(noun, guard, safeguard, champion, sponsor) |
| private eye(noun, expression, agent, spy, informer) |
| private investigator(noun, expression, agent, spy, police) |
| prosecutor(noun, agent, spy, police, informer) |
| protector(noun, guard, safeguard, companion, attendant) |
| reporter(noun, agent, spy, informer, gumshoe) |
| roper(noun, agent, spy, police, informer) |
| safeguard(noun, guard, companion, attendant, champion) |
| scout(noun, verb, bother, agent, chase) |
| sentinel(noun, guard, safeguard, champion, sponsor) |
| sergeant(noun, agent, spy, police, informer) |
| shadow(noun, verb, follow, agent, spy) |
| shamus(noun, agent, spy, police, informer) |
| shepherd(noun, guard, safeguard, champion, sponsor) |
| shoofly(noun, agent, spy, police, informer) |
| sitter(noun, guard, safeguard, champion, sponsor) |
| sleuth(noun, agent, spy, informer, reporter) |