From Inside the Grey House:
When Vincent found out that one of his people were betraying him or in any way hurting one of his own, he let the deceit continue to its fruition. He had the betrayer watched until the full extent of the lies were revealed. Then, when he was sure the betrayer was at his or her peak, Vincent snared the person and exacted revenge befitting the depth of the treachery. Lorraine believed in stopping the deceiver as quickly as possible and found that killing a betrayer swiftly was just as meaningful a deterrent. Consequently, Lorraine hardly ever used her dungeon.