The Prefecture Magisterium (also known as the Malagra) is a division of the Adeptus Mechanicus, acting as its de facto secret police. It is charged with preserving the dogma of the Cult Mechanicus and the persecution of Hereteks. It operates military Cohorts and hunter-killer clades which are maintained on Forge Worlds.

辖区裁判所（也称为马拉格拉）是机械神教的一个部门，是其事实上的秘密警察。它被使用维护机械教派的教条和迫害异端。它在铸造世界上运营着军事大队和猎杀分支。

Agents of the Prefecture Magisterium are known as Arcuitors and are usually Magi themselves. Known for their devoutness to the Cult Mechanicus, these sinister figures are also dubbed the Paternis Malagra or Fathers of the Malagra, for they are often ancient beyond belief and heavily augmented. The Arcuitors do not officially lead the Prefecture Magisterium, but through their actions are the agendas of the organization shaped. A senior Arcuitor can call upon great resources against those they deem worthy of persecution such as the Ossifram Majority or the Dark Mechanicum.

辖区裁判所的特工被称为操肢者，通常是圣贤士。这些险恶的人物以对机械教派的虔诚而闻名，也被称为马拉格拉父辈或马拉格拉之父，因为他们往往是古老得令人难以置信的，并且被大量强化。操肢者并没有正式领导辖区裁判所，但通过他们的行动，该组织的议程得以形成。高级操肢者可以调用大量资源来对抗他们认为值得迫害的人，如骨骼架构派或黑暗机械教。