The campaign thus far: The Acolytes were dropped onto the shrineworld of Reshia to investigate rumors of something calling itself the Night Cult. Being Ordo Hereticus, this is more or less their stock-in-trade, so they figure it'll be a walk in the park. Their Inquisitor, Havelock, says they have a month to find out what they can and, if necessary, exterminate the cult if it is found to be exhibiting Heretical tendencies. During this month they encounter the first few adherents of the Night Cult, complete with the Sarcosan devices on their chests. By hook and by crook they manage to remove the cult with great prejudice and in so doing secure one of the Sarcosan Wave Devices as evidence for Inquisitor Havelock. I can elaborate on that if anyone is interested, but there's a spanner in the works that is the result of bringing back the device, which is being played out currently.
After leaving Reshia and heading to Scintilla for another Conclave, the group is met by Inquisitor Hex of the Ordo Xenos, who claims that they have something that belongs to Ordo Xenos; i.e. the Sarcosan Wave Device. The group insists that they own it by right of conquest, beyond the simple fact that it's considered evidence from their investigations. Hex then leaves them with a subpoena, saying that the device will be his. The group's Arbitrator spent most of the following session researching precedent in both Adeptus Arbites and Inquisitorial libraries (those he had access to, of course), and the actual trial is forthcoming.
Have I presented the group with an opportunity for intricate roleplaying, as they argue in the Courts of the Inquisition, or am I just being a huge jerk? I don't want the whole trial summed up with a few abstract dice rolls, so instead I've scribbled out summations of the trial records that the group has accessed, and assigned a modifier to each established precedent, so that if they still insist on a roll at the very end, it can be done.
The way I see it you have just introduced your group to the wonders and dangers of Inquisition politics. I like the idea of modifiers on the precedents they have discovered and you could do the same depending on the quality of the arguments that they give before the court.