A recent TIL states: TIL that Benjamin Franklin was not trusted to write the Declaration of Independence as they were afraid he would write a joke in it. Are there historical examples of such a thing occurring?

I don't know if it is fair game to answer one's own question... but I just realized that I had heard something that slightly fits this question. While visiting the Vatican, we were told about The Last Judgement by Michelangelo. The painting included nudity and other questionable material, which was frowned upon by the Pope's own master of ceremonies, Biagio da Cesena.

http://en.wikipedia.org/wiki/The_Last_Judgment_(Michelangelo)

To quote the wikipage: " In response to certain accusers, when the Pope's own Master of Ceremonies Biagio da Cesena said of the painting "it was mostly disgraceful that in so sacred a place there should have been depicted all those nude figures, exposing themselves so shamefully," and that it was no work for a papal chapel but rather "for the public baths and taverns," Michelangelo worked Cesena's face into the scene as Minos, judge of the underworld (far bottom-right corner of the painting) with Donkey ears (i.e. indicating foolishness), while his nudity is covered by a coiled snake. It is said that when Cesena complained to the Pope, the pontiff joked that his jurisdiction did not extend to hell, so the portrait would have to remain.[3]"

Edit: A close up of the "portrait."