PARIS — During a recent protest in Marseille, seven people were suddenly surrounded by the police, bundled into a van and brought in for questioning. Their offense was not the demonstration itself but the balaclavas they were wearing, a violation of the French law banning full-face veils in public places, passed in April 2011.

The demonstration was against the conviction of the feminist Russian punk band Pussy Riot, hence the balaclavas, but the law was aimed at what Nicolas Sarkozy, then the president, considered a rise in Islamic extremism in France.

From the beginning, critics warned that the law, in addition to depriving Muslim women of their rights, would further inflame tensions already raised to a high pitch by the economic crisis, riots and lingering fears of terrorism, on one side, and accusations of racism on the other. A little more than a year later, however, defenders and critics agree that the actual impact of the law has been far less dramatic than the politicized prologue, largely because of tolerance from most Muslims and the police.

France’s experience with the so-called burqa bill is in many ways a proxy for the country’s — and Europe’s — ability to integrate its Muslim population, the largest on the Continent. In July 2011, a similar ban took effect in Belgium on the niqab — which covers every part of the face except the eyes, and is popularly and mistakenly called a burqa — and the Dutch government has said it hopes to pass such a law next year.