Isaea's Slavery Document is a quest item needed in the Nalia abducted by Isaea Roenall companion quest. Officer Dirth carries it and you can pickpocket it from him or kill him to loot it.
Content[]
| “ | This document contains a register of slaves recently sold to this outpost of slave lords located in the Temple District. It also bears a signature in wax, pressed by a signet ring. It is the greater crest of the family Roenall, along with the individualized markings of Isaea Roenall. This is damning evidence if it is to be believed. | ” |