Yusuf al-Qaradawi is suing the Abu Dhabi newspaper al Ittihad for publishing numerous articles attacking him for issuing a fatwa authorizing the killing of American civilians in Iraq. Al Ittihad broke the story, which was quickly picked up and disseminated widely. Qaradawi has repeatedly denied making such a statement, but that didn’t stop it from winding its way into the popular conventional wisdom both in the West and in the Arab world.
For responses to the al Ittihad allegation, see for example here, here, here and here.