some stuff about the tal diann :)

The Tal Diann was the internal affairs division of the Romulan Star Navy of the Romulan Star Empire. The Tal Diann reports to the Star Command and serves as a form of naval intelligence separate from the Tal Shiar intelligence service.
The organization was created by the Imperial Fleet as a result of the growing power of the Tal Shiar. This is because of the fleet's belief that trusting the intelligence services good graces would have been unwise and thus Tte Tal Diann polices the fleet. They serve as the counter intelligence wing against Tal Shiar operations who subjected all other organizations, including the civilians, to intense scrutiny.

The head of the Tal Diann is known as the Chief of Military Intelligence who holds the rank of Admiral within the Imperial Fleet. The CMI sits on the High Tribunal, something that has been an annoyance of the Tal Shiar. The Chief of Military Intelligence also reports directly to the Praetor. Junior positions include Chief of Planetary Forces Intelligence, Chief of Stellar Forces Intelligence, and Chief of Operations. (LUG RPG: The Way of D'era: The Romulans)

The most visible members of the Tal Diann were the legates or belisaro. Each ship is assigned a belisaro who serve as the Star Command's eyes and ears. During times of war belisaros take command of the unified Star Navy so to maintain the political balance. They serve in the Praetor's name and have ultimate authority in matters such as promotions, troop movements, strategies and other war duties. (The Dominion War Sourcebook: The Fires of Armageddon)

Interesting read, i like your spin on your internal workings

easy there, not my take just the breifest most concise copy-paste i came across during research