It's easy to be classified as having bipolar disorder. Despite it being a big looking word, it is actually as common as flu. If someone's mood is swinging a little too often and doesn't have the capacity to moderate the swings, it can be medically classified as bipolar disorder. Bipolar disorder can be short term (event based) or long term.
What I meant in my previous post is that, regardless of bipolar disorder or otherwise, it is inexcusable to steal. Even kleptomaniacs goes to jail, so what is bipolar disorder to be used as an excuse to stealing?