The Galactic Federation is the prominent interplanetary government of the Metroid universe. Specifics of the Galactic Federation's governing structure and history are vague; various background materials place it as being started by mankind before other species joined it in the hopes of a stable society. Supposedly, all government matters are discussed by a senate. It is not known if the Galactic Federation is led by a singular role such as president or prime minister.
Though the role the government plays is fairly minor in the majority of the Metroid titles to date, it has been revealed that there is a certain level of corruption within its ranks. In Metroid Fusion, it is revealed that the Federation attempted to hinder Samus Aran's mission to destroy the X-Parasites and SA-X on the BSL Research Station so that both could be collected for research purposes into military application. However, Samus foils the government's plans by crashing the station into the surface of SR388, destroying all traces of the X on both the station and the planet.
A similar plot is unveiled in Metroid: Other M. Following Samus's adventures in Super Metroid, a Galactic Federation quarantine officer cleans the remnants of the baby Metroid and other creatures from her armor. This is ostensibly done in order to make her more presentable to Galactic Federation officials to whom she is to report. However, the true purpose behind this move was to collect the Metroid's DNA samples for use in bioweapon research authorized by certain unknown members of the government.
Depiction of the Federation Military
The Galactic Federation military first played a more prominent role in the Metroid Prime series. Metroid Prime 3 in particular introduced a number of Federation military elements, including weapons, vehicles, and non-combat uniforms. The military's standard-issue power armor was first seen in Metroid Prime 2, and a newer model of armor was used in Metroid: Other M. All soldiers seen throughout the Metroid series thus far are human, with no indication of any other species serving in the military. A stylized cross serves as a symbol of the Galactic Federation Army.
Following mission briefings, it is customary for the members of GF military squads to give their commanding officers a thumbs up in recognition of the mission objectives. However, during her military days, Samus, still young and rebellious, would routinely respond to her commander Adam Malkovich with a thumbs down.