SAO PAULO—A Brazilian judge is urging prosecutors to fine a small-town mayor who rode a donkey to his inauguration to needle an opponent who allegedly referred to him as a "burro" in a debate.

Judge Luciane Glesse says that Passa Sete Mayor Vaderlei Batista should be fined $250 for ignoring a restraining order barring any further donkey business from local politics following the October elections.

Batista says his campaign rival referred to him as a donkey in a debate, and he responded with offensive phrases that likened the opposition party to a donkey. That prompted the rival candidate to seek a court order against such satires.

Batista says that he promised voters to ride a donkey to this week's inauguration.