The Spectres were chosen from the finest salarian Special Tasks Group operatives and asari huntresses, intended to function partly in an observational capacity, but also as the Council's first line of defense. The Office of Special Tactics and Reconnaissance branch was founded in 693 CE, shortly before the Krogan Rebellions began, at a time when the Council was uneasy about the unchecked expansion of the krogan into Citadel space. Assignment of a Spectre is less contentious than military deployment, but makes it clear that the Council is concerned about a situation. Only after the Krogan Rebellions did their activities become publicized. For many years, they operated in secrecy, as back-room 'problem solvers'. The Spectres were founded after the salarians joined the Council.

All get the job done, one way or another, often operating outside of the bounds of galactic law. Others are cold-blooded assassins, ruthlessly dispatching problem individuals. Some are empathetic peacekeepers, resolving disputes through diplomacy. They operate independently or in groups of two or three. Each Spectres are handpicked from various Council races and are granted the authority to deal with threats to galactic peace and stability in whatever way they deem necessary, including the power of life and death over the inhabitants of the Milky Way Galaxy. Spectres are elite agents from the Office of Special Tactics and Reconnaissance, a branch of the Citadel Council as well as its successor, the Interstellar Republic. Individuals forged in the fire of service and battle-those whose actions elevate them above the rank and file.' ―Citadel Councilor Valern

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