Captain Exley was the commanding officer of a Federation capital ship who lived during the late 24th century.
In 2381, Exley and his first officer, whose shoulder he sat upon, attended the Command Conference on Starbase 25. Ensign Brad Boimler, posing as William Boimler, spied him at the afterparty held in Ballroom Alpha.
He was later chatting with Captain Anderson when the Doopler emissary was beamed into the ballroom and began dooplercating. (LD: "An Embarrassment Of Dooplers")