Joan Rivers Joan Rivers

Put a camera on Joan Rivers and just let it roll, because the comedian just can't keep her mouth shut.

Following an appearance at a New York City bookstore where she officiated a gay wedding, Rivers was asked by a reporter if there would ever be a gay U.S. president and she just couldn't resist making a crack.

"We already have it with Obama, so let's just calm down," Rivers said.

Unprompted, Rivers continued, this time making Barack Obama's wife Michelle her target. "You know Michelle is a tranny." When asked to clarify, she said, "A transgender. We all know."

The outspoken Rivers has been known to make controversial comments. In just the last few years, she's made fun of Lindsay Lohan's miscarriage, the Ariel Castro kidnappings and singer Adele's weight.

What do you think of Rivers' comments?

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