David Cole is the national legal director at the ACLU and the George J. Mitchell professor at Georgetown University Law Center. He is also the legal affairs correspondent for The Nation, and a regular contributor to the New York Review of Books.

People hold signs saying ‘Je suis Charlie’ as crowds gather at ‘Place de la Republique’ for a vigil following the terrorist attack on Jan. 7 in Paris. Twelve people were killed, including two police officers, as two gunmen opened fire at the offices of the French satirical publication Charlie Hebdo. (Marc Piasecki/Getty Images)

In the wake of the recent terrorist attacks in Paris, the principal message has been, quite rightly, to defend free expression and to condemn those who would use violence to respond to messages they dislike. Yet at the same time, the French Ministry of Justice has ordered prosecutors to enforce with “utmost vigor” a law that itself imposes violence, albeit of the state-sanctioned variety, on speech whose messages the French majority dislikes.

“Do as I say, not as I do,” the French seem to be saying. But as every parent knows, that advice almost always backfires.

French law makes it a crime, punishable by up to seven years in prison, to speak in support of terrorism. One need not threaten imminent violence of any kind.  According to the New York Times, as many as 100 people, presumably most of Muslim faith, are under investigation for making comments that appear to support terrorism in the aftermath of the Paris tragedy.

One man, a French-Tunisian, has already been arrested, tried, and sentenced to six months in prison for shouting out in public while passing a police station:

They killed Charlie and I had a good laugh. In the past they killed Bin Laden, Saddam Hussein, Mohammed Merah and many brothers. If I didn’t have a father or mother, I would train in Syria.

Another man, a notorious satirist himself, Dieudonné M’bala M’bala, will go on trial next month for posting a Facebook message saying, “Tonight, as far as I’m concerned, I feel like Charlie Coulibaly.”

Such statements may be tasteless. But the same could be said of much of what Charlie Hebdo publishes. That’s, at least in part, the point.  Yet at the same time that millions of French citizens are vocally defending the right of cartoonists to engage in provocative speech, their government is prosecuting Muslims for doing just that. Locking someone up for six months, or even seven years, is not the same thing as gunning him down in cold blood, to be sure – but both use force rather than reason to respond to the expression of an idea.

The French don’t have our First Amendment, but they do have Voltaire; they should know better.

Penalizing speech in the wake of violence that spreads fear is not new. The United States prosecuted anarchists in the early 20th century after a series of bombs exploded in multiple cities across the country, including one that blew off the front of the Georgetown home of Attorney General A. Mitchell Palmer. In World War I, the United States made it a crime to speak out against the war, and punished pacifists and communists who did no more than publish leaflets objecting to the war. The most famous victim of that law, Eugene Debs, the head of the Socialist Party of America, was sentenced to 10 years in prison for praising the courage of draft resisters.*

These reactions are understandable. As Supreme Court Justice Oliver Wendell Holmes Jr. once wrote: “Persecution for the expression of opinions seems to me perfectly logical.  If you have no doubt of your premises or your power, and want a certain result with all your heart, you naturally express your wishes in law, and sweep away all opposition.” But Holmes was speaking ironically. The passage comes from his dissent in a case penalizing anti-war speakers, widely seen as the foundation of free speech jurisprudence in the United States today.

The French seem to have missed the irony.

Penalizing speech is also a common reaction to violence. When a community is in fear, its leaders often respond preemptively and preventively, by rounding up suspects not based on harmful conduct, but based on speech or association. We did exactly that after the bombing of Attorney General Palmer’s home, rounding up and deporting thousands not for violence, but for their communist or anarchists views or ties. We did it again after the Sept. 11, 2001, terrorist attacks, using immigration law to lock up and deport thousands of Arab and Muslim immigrants without finding a single terrorist among them.

But such responses are fundamentally ill-advised. Punishing the expression of dissent will not eliminate dissent and dissatisfaction. At best, it merely drives it underground, where it is more difficult to identify and respond to. At worst, it prompts dissidents, robbed of peaceful means of expressing their views, to take more violent measures. The best remedy for offensive speech is condemnation through more speech, not resort to state force. For these reasons, the U.S. Supreme Court in the 1960s ruled that one cannot be punished, even for advocating violence, unless one’s speech is intended and likely to spark imminent lawless violence, a speech-protective standard. It’s not that the court values violence, but rather that it recognizes how easily such laws can and are used to punish dissent.

The French don’t have our First Amendment, but they do have Voltaire; they should know better. They have proudly proclaimed, in the wake of the Charlie Hebdo incident, their commitment to tolerance even of offensive speech. Except, it appears, when it is spoken by Muslims.

* Correction: An earlier version of this story misidentified the name of the Socialist Party of America.