Sisters of Silence - Sisterhood Organisation: The Divisio Investigates is an organisation more akin in structure to the fusion of an agency of legal enforcement and a secret society or secular military order of old. As with so much that surrounds those who orbit close to the centre of the Emperor's work, its ways and dispositions are all but impenetrable to outsiders beyond certain open ranks and divisions observable by those who were called to fight alongside them.A complete accounting of the Sisters of Silence's ranks is then impossible, but the simple extrapolation of logic from the notional size of the League of Blackships required at the minimum for the Great Tithe to function, as it assuredly does, places the Sisters of Silence at tens of thousands of active Witchseekers.The high command of the order outwardly comprised three high offices and individuals that were known to the hierarchy of the Imperium at the time of the outbreak of the Horus Heresy, though doubtless there were others that went unknown outside of the Sisterhood itself. Most famed of these is the rank of Knight-Commander; the most senior field officer of the Silent Sisterhood. This title was held by one of the most sinisterly renowned warriors in the Imperium -- Jenetia Krole, known also by popular myth as the "Soulless Queen."Of equal importance to the execution of the Great Tithe is the rank of the Mistress of the Black Ships, and in effect, the grand admiral of the Divisio Investigates fleet; this was held by Varonika Sulath.Lastly is the Nemesis Praxia, Ebon Naroda; she who was high guardian of the compiled lore and estates temporal of the Divisio Investigates, and ultimately responsible for the training of its acolytes.Other ranks within the organisation progress through that of Acolyte -- of the First, Second and Third rank -- more informally known as "Sisters-in-Waiting," who had not yet formally been initiated into the order. Further ranks of the Sisterhood proper were referred to with melodramatic flourish as the "Null Maidens" by the Remembrancers of the Great Crusade. These are structured both in terms of seniority and tactical disposition, ranking in order: Seeker, Prosecutor, and with Vigilator as the most senior of the three.Other specialist units such as the Pursuers, the Aquilai Astra and Questora, accounting for cyber-beast handlers, pilots and void crew, and Investigators/Enforcers, respectively, branch off these.The Chamber of Vigilance was the largest of all the sub-orders of the Sisterhood, and its sisters acted as the garrisons and collectors of the Great Tithe.The Chamber Astra captained and guarded the Black Ships. Unlike the rest of the Silent Sisterhood, the sisters who comprised the Chamber Astra were never scattered or abandoned by the Imperium after the Horus Heresy and continued to perform their essential duties throughout the Age of the Imperium.The order's hierarchy next bifurcated to outside eyes into two distinct groups dedicated to specific martial tasks: the Chamber of Oblivion and the Chamber of Judgement. The first was an elite militant sub-faction of the Sisterhood comprising the most powerful psychic Nulls and most martially skilled of Vigilators, and from its ranks of Oblivion Knights and Knights-Centura the battlefield commanders of the order are taken.The latter martial chamber, the Chamber of Judgement, is if anything more feared. It comprises the dreaded Silent Judges of the Excrutiatus, whose task is to weigh the actions of the guilty and innocent when it comes to those concealing psykers from the tithe, and where matters are not clear regards those believed to be psykers, to determine the presence of the psyker's gift, and where it is found, to pass judgement on whether the accused should be taken by the tithe, or executed as a danger to Humanity.