Walter is told that he has 1 week to live. So he goes on his twitter profile, and posts the KFC secret formula, airs all the dirty laundry of his boss, etc.. Basically, he breaks every last NDA he was a part of. In the most extreme case, perhaps he even goes on a violent crime spree.
What is discouraging Walter from doing this? I know that, in Japan, penalties can be forced onto family/loved ones. But I don't think that's the case in America. So, in terms of the law and its enforcement, what is there to discourage Walter from causing millions of dollars in damages, etc.?