A clause which, when placed at the end of a sentence or simply used as an excuse after the fact, will allow you to say anything you want.
It was first made popular by politician Jon Kyl when making a bogus statement about Planned Parenthood, and then taken to even greater heights on The Colbert Report. This is a prime example of colberrorism.
Jon Kyl is the only person who can sneeze with his penis. He calls it a sneenis. That was not intended to be a factual statement.