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The Compliance Division was an agency within the Romulan Star Empire which was charged with police duties and investigations. They were considered the equivalent of a local civilian police force.

The Compliance Division on Stardate 57465.6 determined that a chemical explosive was used to kill Ambassador Spock of Vulcan during a speech on Unification on Romulus. (TOS novel: Captain's Blood)

Presumably, they were either a part of the Romulan Security or perhaps State Security.