(AP Photo/Michel Euler)
As the husband of supermodel-turned-pop star Carla Bruni and friend to some of France's most powerful media figures, Sarkozy has long basked in his cozy ties with the entertainment industry, which has embraced the measure.
But many in Europe have denounced it, saying government controls needed to enforce the law could open the way for invasive state monitoring that violate privacy. And legal challenges at home could derail it: The opposition is trying to get the law declared unconstitutional.
Music, film and other industry groups have welcomed the measure. Critics, however, worry about civil liberties.
Some Internet experts say the law will be technically impossible to apply. It requires Internet subscribers to install software that would enable authorities to track down and identify those suspected of illegal downloads, but some experts say such programs do not exist.
And because it denies accused pirates the chance to defend themselves before their web connections are severed, legal experts say it will not stand up in court.
The measure's first test came Tuesday, when the opposition Socialists took their objections before the Constitutional Council, which has a month to issue a ruling. If the council decides the law does not violate the constitution, it could take effect by summer.
It calls for graduated reprisals against alleged offenders. If a suspected pirate fails to heed e-mail warnings and a certified letter, Internet access would be cut for two months to a year -- with the subscriber required to keep paying for the service under the contract's terms.
In the United States, the music industry has waged war on content swappers with limited success. A campaign to sue individuals who repeatedly download free songs was dropped last year in favor of an effort to work more closely with Internet service providers to try to block connections of alleged offenders.
Before the French legislation was approved, it encountered resistance in the European Parliament. Elections for a new parliament take place in June, and the fight for Internet freedom has become a campaign issue in some countries, notably Sweden, which has gained a reputation as a hub for illegal file-sharing.
Support for Sweden's Pirate Party, which calls for legalization of file-sharing, is growing, and a recent poll shows the party could gain a seat in the European Parliament.
Christian Engstrom, the party's nominee, said the French law is damaging to the free exchange of information on the Internet.
French cooperation with the "greedy copyright industry is not fitting for a Western democracy," he said.
With the exception of Sweden, where a court sentenced four men last month to one-year jail terms for helping people download copyrighted material, court cases in Europe have failed to dent the practice. A Spanish court this week will hear the latest industry case against suspected file-sharers.
Russia and Ukraine are some of Europe's biggest offenders in illegal file-sharing. However, they have no intention of passing legislation similar to that in France and are out of the reach of eventual European Union rules.
Last year, the Russian government did shut down one music download site, but it soon resurfaced under a different name.
The French law faces opposition not only from politicians and the public. Internet service providers in Britain consider cutting offenders' connections a disproportionate, and ultimately impractical, punishment.
"Significant technological advances would be required if these measures are to reach a standard where they would be admissible as evidence in court," the U.K. Internet Service Providers' Association said Tuesday.
ISPs in Germany have so far refused to volunteer information about Internet pirates, forcing copyright owners to take them to court to compel them to reveal identities.
In the United States, Internet service companies complain that big users of music and video-swapping sites are clogging their networks, and some have begun to impose caps on Internet usage and charge extra for customers who exceed it.
In France, opponents say the new law misses the point by targeting downloads rather than online "streaming" -- an increasingly popular approach where music and videos are played over the Internet, rather than downloaded and saved onto a user's computer.
The French law creates a government agency to sanction offenders, with the actual monitoring left to industry watchdogs.
"It has been extraordinary to see the change of attitude to this problem, not only among governments but also within our own creative industries," John Kennedy, chairman and chief executive officer of the International Federation of the Phonographic Industry, told The Associated Press in an e-mail statement Wednesday. "Barely two years ago Internet piracy was something that seemed to many beyond regulation. Today, the mind-set couldn't be more different."
Associated Press writers Scott Sayare in Paris, Malin Rising in Stockholm, Jane V. Hardy in Vienna, Matt Moore in Frankfurt, Raphael Satter in London, Constant Brand in Brussels, Maria Danilova in Kiev, Vladimir Isachenkov in Moscow and Ciaran Giles in Madrid contributed to this report.