BERLIN — A murder spree in France by a gunman inspired by al Qaeda Internet sites has European experts debating proposals to criminalize the act of regularly visiting terrorist Web pages.
French President Nicolas Sarkozy called for new legislation last week that would punish people who "habitually consulted" websites that advocate terrorism or incite hatred and violence.
The move followed the killing of three Jewish children, a rabbi and three French soldiers by Mohamed Merah, 23, before police fatally shot him during a 32-hour standoff at his home in southwestern France.
Many analysts say Mr. Sarkozy's initiative is "ludicrous," and some questioned the feasibility of widespread Internet monitoring.
"You have to understand that this is just an announcement because we are in a presidential campaign, so I don't think it's going to be transformed into a new law," said Eric Denece, director of the French Center for Intelligence Research in Paris.
"The French now permit police to arrest people before they commit an attack, and that is enough for the time being. Most of the lawyers and judge and prosecutors say that this new project is absolutely stupid and will probably be ineffective."
Mr. Sarkozy is in a tight race for re-election in voting scheduled in April and May.
Extremist websites have been often been cited by government officials and analysts as the source of inspiration for would-be terrorists. The Web pages provide a means of research, contact and communication for various terrorism groups. The killings in Toulouse, France, have sparked a renewed debate in Europe on what to do about them.
"We've begun to see a bigger debate around online networking. We're beginning to enter into a debate around cybersecurity in relation to extremism," said Matthew Goodwin, who specializes in studying extremism at the University of Nottingham in Britain.
"The responses across Europe vary, but what we are seeing is a growing interest around the tools that extremist groups use, whether Internet sites or social media or networking."
In 2002, the European Union adopted rules to combat terrorism, compelling member states to introduce legislation that criminalizes preparing and training for a terrorist attack.
"There are no holes in the legislative net anymore. We can prosecute and prohibit almost everything connected to terrorism," said Beatrice de Graaf of the International Center for Counterterrorism in The Hague, who did a recent comparative study of counterterrorism measures.
"The point is not a lack of legislative measures. The problem is living up to these laws, monitoring these sites, assessing and analyzing and processing all the material."
Large-scale monitoring of the Internet would lead to high costs for governments and threaten people's privacy, analysts say.
"Targeted surveillance is much easier than mass surveillance; but if you wanted to try to capture people you don't know about, the problem is, who are you going to include - the population as a whole or people on incredibly vague suspicions?" said Peter Sommer, who specializes Internet issues at the London School of Economics.
Meanwhile, digital-rights campaigners say plans to go after people visiting the websites, rather than those producing the sites, are wrongheaded.
"The first thing that needs to be established is what is legal or not. If somebody is generating content that is illegal, then the person who is committing that offense is the person that you should go after, not the people who, for whatever reason, end up on a particular website reading it," said Joe McNamee of Digital Civil Rights in Europe.