From wiki,
During the production of the episode "The Littlest Tramp", editor Tom Klein expressed concern that a sequence showing Mighty Mouse sniffing the remains of a crushed flower resembled cocaine use. Bakshi did not initially view the footage; he believed that Klein was overreacting, but agreed to let him cut the scene. Kricfalusi expressed disbelief over the cut, insisting that the action was harmless and that the sequence should be restored. Following Kricfalusi's advice, Bakshi told Klein to restore the scene, which had been approved by network executives and the CBS standards and practices department. The episode aired on October 31, 1987, initially without controversy.
On June 6, 1988, Donald Wildmon, head of the American Family Association (AFA), alleged that "The Littlest Tramp" depicted cocaine use, instigating a media frenzy. Concerning Bakshi's involvement with Mighty Mouse: The New Adventures, the AFA claimed that CBS "intentionally hired a known pornographer to do a cartoon for children, and then allowed him to insert a scene in which the cartoon hero is shown sniffing cocaine." Bakshi responded, "You could pick a still out of Lady and the Tramp and get the same impression. Fritz the Cat wasn't pornography. It was social commentary. This all smacks of burning books and the Third Reich. It smacks of McCarthyism. I'm not going to get into who sniffs what. This is lunacy!"
Bakshi defended the episode, saying, "I despise drugs. I would be out of my mind to show a cartoon character snorting cocaine in a cartoon.", and stating that Wildmon had interpreted the scene out of context. "Mighty Mouse was happy after smelling the flowers because it helped him remember the little girl who sold it to him fondly. But even if you're right, their accusations become part of the air we breathe. That's why I cut the scene. I can't have children wondering if Mighty Mouse is using cocaine." On CBS's order, Klein removed the sequence from the master broadcast footage.
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