Fun glitch happened today. Had just finished the Mind of Madness quest when I went up to see the Jarl of Solitude. Guess what? The old, Imperial-pledged Jarl I kicked out of Whiterun was there too, with his court. They attacked me, and so did all of Solitude's guards for no reason. After that, a character randomly had me pay a 40 G bounty and I was transported back to the prison. When I went back to the Blue Palace in Solitude, the Whiterun Jarl was already gone.
Such a typical Bethesda-like bug.