It's brand-damaging for the government to, for example, represent sexual predators of underage people (speaking here of accusations against Nery Garcia Linares, not the U.S. President) represented as Pokémon, especially with children as Pokémon's primary audience. Nintendo has successfully won several cases in similar scenarios by invoking brand tarnishment.

Can you link to the most similar of those cases? I would assume that most parody would risk tarnishing a brand.