Almost 4 million people marched in France last week to condemn terror and defend free speech after Islamic gunmen in Paris staged a murderous attack on the office of the satirical weekly Charlie Hebdo.
The three-day rampage, which also targeted a kosher store, claimed 17 victims.
Days after the nationwide rallies, controversial French comic Dieudonne was detained over comments in which he appeared to sympathize with the gunman who killed four hostages at the Paris kosher store.
The probe against Dieudonne, whose shows are peppered with racist and anti-Semitic jokes, has sparked accusations of double standards and raised complex questions about the limits of free speech.
"One can perceive this as a contradiction, a small but undeniable minority in France definitely sees it that way," says Eric Mandonnet, a deputy editor and political specialist at France's L'Express magazine.
"There were rallies for freedom of speech in Paris and other cities which were among the biggest demonstrations in the history of France, and one could think that the probe against Dieudonne is also related to free speech."
French prosecutors have opened an investigation into remarks made by the comedian following the massive free-speech rally in Paris.
"I feel like Charlie Coulibaly," Dieudonne wrote in a Facebook post, merging the now-viral slogan "I Am Charlie" with the name of the gunman who killed the four Jewish hostages along with an unarmed female police officer.
The comment has divided his fans, some of whom accuse the government of selectively applying free speech principles while others say the comic has simply gone too far.
It was taken down after less than an hour.
Investigators will now determine whether Dieudonne breached a French law which forbids "condoning terrorism."
The offense can carry a jail term.
Authorities have insisted that France's attachment to freedom of expression does not excuse incitement to terrorism and hate speech, which is also illegal under French law.
In an emotional speech to the National Assembly, Prime Minister Manuel Valls said there should be no confusion between what he called the "impertinent" satire of Charlie Hebdo and Dieudonne's remarks.
"Racism, anti-Semitism, historical revisionism, and condoning terrorism are not opinions, they are crimes," he declared.
Valls pledged a "ruthless fight against terrorism" but said France would also take firm action against "speech that kills."
This determination is already apparent.
More than 50 people have been detained for defending terrorism since last week's attacks. Some of them have been convicted, including a man who was sentenced to four years in prison after praising the Paris gunmen in a drunken rant.
Dieudonne, because he made the comment on the Internet, faces even tougher penalties -- up to seven years in prison and a $118,000 fine.
Local authorities in several French cities have sided with the government by announcing their decision to ban his shows that mock Jews and belittle the Holocaust.
This is not the first time the comedian has been probed for "condoning terrorism." Last September, an investigation on the same charge was opened against him after he mocked the execution of U.S. journalist James Foley by ISIS militants.
Dieudonne is perhaps best known for popularizing the "quenelle," a gesture that resembles a Nazi salute and has since been used outside synagogues and Holocaust memorials.
The gesture drew international attention in 2013 after footballer Nicolas Anelka performed it during a English Premier League match.
The comic, who has been fined multiple times for making anti-Semitic comments, routinely accuses authorities of seeking to muzzle him.
In the wake of last week's massive rallies for free speech, Dieudonne's claims that French authorities violate his freedom of expression are likely to strike an even deeper chord among the disgruntled youth that constitutes his core audience.
"A huge effort to educate people must be made," says journalist Eric Mandonnet. "In certain French suburbs where Dieudonne is seen as a rebel hero, these actions from the French judiciary are absolutely not understood."