A cognitionibus
In Ancient Rome, a cognitionibus was one of the four offices in the chancellor's Imperial Rome office that helped the emperor in his judicial function. It was a formal office function, like the ad legationes.
With the restoration in Hadrian's era, it is possible that the office a libellis dominated the other three: a cognitionibus, a studiis and a censibus. A studiis was a documentation office, and a cognitionibus was the office that studied the process of the emperor's appeal. A correspondence office and an office that controlled the Roman Empire's finances existed.
In the Third century the offices of a libellis and a censibus or a libellis and a cognitionibus were merged.
Marcius Agrippa was a cognitionibus and ab epistulis of Caracalla.