A bouncer at Starbase 25
A bouncer was an individual responsible for regulating access to an event or facility. They were empowered to limit entry to an event to authorized persons.
In 2381, on Starbase 25, an individual was responsible for limiting entry to the Command Conference after-party to Starfleet personnel assigned to Luna-class starships or above. As part of this, Carol Freeman, her senior staff, and Beckett Mariner were denied entry. Entry was granted to Brad Boimler, who was pretending to be his transporter clone William Boimler from the USS Titan. (LD: "An Embarrassment Of Dooplers")