To break the law against a law breaker is not breaking the law.

Captain Rationalization to the rescue!

TBH I only did the Frost quest because I wanted the damn horse, got spoiled by Shadowmere the last time around and I'm not willing to stain my soul with the DB stuff again just to get him/her back. Frost seemed like a reasonable alternative for my current PC, Maven gave me permission to take him, and the mercenaries I killed at the lodge attacked me first.
OTOH I did use the key that Sibbi gave me to clear out their strongbox. But, you know, he GAVE me the key. Plus I RPed that she was secretly helping fund Imperial efforts to take back Riften, and the stuff in the strongbox was earmarked for that. So... it's all good.
