What are the typical duties of Rear Admirals in Starfleet?

Question

In Starfleet, a Captain-rank officer typically serves as the Captain of a Starship. Of course there are also lots of Captains in other positions, especially on planets and in Starbases, and perhaps one could characterize "non-ship-captaining captains" as well, but still.

My question is: What do Rear-Admirals typically do in Starfleet? What are their typical duties, as opposed to Vice-Admirals on one hand, and Commodores on the other? Or - is it the case that all admirals are basically the same in term of duties, and its just a matter of time served in the rank?

Answer 1

Starfleet (or rather Star Trek writers writing about Starfleet) tends to treat all admirals as being functionally the same, with Rear-Admirals and Vice-Admirals usually in charge of facilities mentioned, but often unseen, and significant plot events such as investigations and courts martial.

• Rear-Admiral Brand served as Superintendent (Chief Administrator) of Starfleet Academy on Earth. She was seen to coordinate a 'board of enquiry' at the Academy after the accidental death of a student.

• Rear-Admiral Cole (in Kirk's time) was responsible as the Supervisor of Curriculum at Starfleet's Training Academy.

• Rear-Admiral Minor (in Kirk's time) was responsible as the Commodante [of] Cadets at Starfleet's Training Academy.

• Rear-Admiral Norah Satie was responsible for a wide-ranging investigation of Starfleet officers suspected of sabotage and espionage.

• Rear-Admiral Bennett served as Judge Advocate General to Starfleet.

• Rear-Admiral Rollman commanded Starbase 401.

Answer 2

Note: This is a speculative answer which needs backing up.

Perhaps we should think of the "stereotypical", or perhaps the namesake-traditional, duties of a Rear Admiral - by borrowing from the original naval tradition which gave rise to this rank.

Well, in a squadron of starships,

• The squadron commander would be a (four-star) Admiral, commanding from the center vessel and directing the squadron's activities.
• A (three-star) Vice-Admiral would assist the Admiral and commands the lead ships, bearing the brunt of the battle.
• A (two-star) Rear Admiral would command the ships at the rear. Since those ships are in the least danger, this officer is the most junior, typically, of the three flag officers.

And just like Captains don't always captain a ship, so do rear-admirals aren't always busy commanding the rear part of a squadron-of-ships. Perhaps even more so, since most Starfleet ships don't seem to be operating in squadrons.