What is the worst Public Relations marketing scheme you have ever come across?

This industry of marketing people and products is not always pure and straight forward. I understand things can get exaggerated or mistruths and/or misrepresentations can occur in the name of getting noticed in the public eye. Lives and reputations can get damaged because the competition can get tough for the money and the success involved in being a “good” PR consultant. What’s the worst public relations campaign you have ever come across and how did you find out that it wasn’t necessarily “the truth”? p.s. And I’m not just talking celebrity PR.