Determining how far to go in trying to keep the comedian from spreading his vision and assessing how to gauge when those efforts are counterproductive are among the tricky tasks facing the French authorities. At the same time, right-wing populists, some of whom similarly hold anti-Semitic views, seem poised to make electoral gains across much of Europe — and not least of all in France, where the far right National Front has a higher approval rating than the other two major parties.

Freedom of speech is less protected in France than in the United States, and there is widespread support for seeking to muzzle Mr. M’bala M’bala. But his case has set off a new debate over the limits of free expression, with advocates for civil liberties asserting that the government risks overreacting and endangering basic freedoms as well as adding to his luster by making him into a martyr. Lawyers say they are particularly concerned that the government has pre-emptively banned his shows.

“These preliminary injunctions that have been pronounced against his shows are dangerous not for Dieudonné, but because citing ‘a risk to public order’ opens the way for other similar injunctions,” said Agnès Tricoire, a lawyer who specializes in intellectual property and freedom of expression and represents the French League of Human Rights, a group that has a more American and British view of freedom of expression.

Ms. Tricoire noted that two of the legal grounds for complaints against Mr. M’bala M’bala are highly subjective: that he is a threat to public order and that his performances defame the humanity of a group or community. He has also been accused of denying the Holocaust — a crime in France — and of inciting hatred.

“The notion of violating human dignity is claimed by certain pressure groups who want to forbid performances for moral reasons,” she said, noting that a similar argument could be used by the far right to try to prohibit art shows or theater even before a performance because those groups view them as immoral. So far, the French government has refrained from bowing to such pressure, even going so far as protecting audiences from protesters when they object to artistic performances.