Starfleet Security: policing the borders, bases, facilities and starships of the United Federation of Planets.
Whereas Starfleet Tactical is the defensive aspect of Starfleet, with peacekeeping and war-fighting capabilities, Starfleet Security is like a cross between the U.S. Coastguard, the Police, Customs & Excise and the Federal Bureau of Investigation. These are the police on starships and starbases and have specialist uniforms for the role.
Part of Starfleet Security is the internal monitoring of the Federation for criminal activities, with monitoring stations located across the Federation and along the border, looking for smugglers, traffickers, slave traders and illegal immigrants. Their Peel class Okinawa-variant police frigates have no photon torpedoes but they do have sensor probes to aid in their role. In addition to the Peel class Okinawa-variant police frigates, Starfleet Security also has Strider class police-variants as well, similarly fitted only with Phasers.
Starfleet Security is best known for the armoured security officers policing the starships and starbases of Starfleet. The additional appeal of the Security path is the early opportunities for command on their starships; Lieutenants and Lieutenant Commander-rank individuals can command patrol vessels of Starfleet Security.
Admiral Edward Blackmore is the current head of Starfleet Security.
Roles of Starfleet Security:
Patrolling shipping and border control
Defence of the Federation internally
Policing and anti-trafficking