23. Michael Moore Booed (2003)

While accepting the Oscar forBowling for Columbine, Michael Moore raged against the Iraq War from the stage. Booing erupted throughout the hall, countered by cheers, creating a chaotic back-and-forth that drowned out parts of his speech.
The political rant turned the acceptance into a divisive spectacle and one of the most uncomfortable audience reactions in Oscars history.