Muslim prayers in the streets of Paris? Row upon row of worshippers under the eyes of uniformed French policemen? Hundreds of men chanting "Allahu akbar" in open-air mosques? A series of videos posted online over the past two years, depicting all of the above, by a journalist using the pseudonym "Maxime Lépante" have provoked a mixture of shock and disbelief. For at least 15 years, local officials have been collaborating with the police department to tacitly authorize the obstruction of a few narrow streets in Paris's 18th arrondissement—Rues Myrha, Léon, Polonceau, Poissoniers—to accommodate overflowing crowds for midday prayers on Fridays. Similar "tolerance" is exhibited by several other French towns and cities.

Illegal street prayers became a national political issue last December when Marine Le Pen—who in January replaced her father, Jean-Marie, as president of the National Front party—denounced them as an "occupation without tanks or soldiers." Since then, the question has broadened to a critical examination of Islam's role in French society, becoming a major issue going into the 2012 presidential campaign. Ms. Le Pen's rising poll numbers place her neck and neck with President Nicolas Sarkozy and likely Socialist candidate Dominique Strauss-Kahn, and the weak performance of Mr. Sarkozy's UMP party in this weekend's local elections have laid further ground for a shake-up at next year's polls.

Read the complete original version of this item...