Had an amusing situation when a dwarf was brought in for interrogation at the very moment when he was trying to steal an artifact. He confessed to intention and revealed a mastermind behind the plan. Immediately after that he procedeed and stole the artifact anyway.
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Some continuation.
So after confession the dwarf went and stole the artifact. He then met the ringleader, they did a little dance in the hallway, and the artifact changed ownership. Unfortunately, my captain of the guard went to sleep right after the interrogation and was unable to catch up with the guy, who quickly embarked on leaving. My military squads managed to intercept him on the edge of the map and took him off. The artifact was returned, the body was dumped into magma, and i thought i'd never be able to find out what that all was about now that the ringleader was dead. However rather soon i noticed captain of the guard heading his way out towards the place where the plotter was killed. He stood there for a brief moment, went back to his office (alone) and came up with an interrogation report with information... from the dead guy.
Possibly i ordered CotG to interrogate him before CotG went to sleep, so he proceeded with the order on waking up, and it worked out despite the subject was already deceased.
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Preemtive interrogation uncovered a plot that hasn't yet come to motion. 447 days in prison for espionage. That's rough.