European governments invariably claim that Sharia law doesn't operate under their jurisdictions.
Officially, that may be true.
But at street level, in towns and cities across the continent, unofficial Sharia courts operate with impunity, and self-appointed Sharia patrols or 'morality police' strictly enforce Islamic decrees, often using threats of violence.
For months, Muslim youths seeking to impose a 'Shariah zone' threatened, extorted and harassed bar owners in Nørrebro, Copenhagen, smashed windows and vandalised premises.
Police initially showed little interest in tackling them.
Heidi Dyrnesli from Cafe Heimdal recounted:
Recently some young men came into the bar and shouted that all guests should leave. They shouted so that the site belongs to them and that Nørrebro is Sharia zone, so there is no drinking alcohol.
Though no organised Sharia patrols have yet come to light in France, gangs of Muslim youths are increasingly assuming the role of morality police:
For years now, 'big brothers' have been obliging their mothers and sisters to wear a veil when they go out. And now that this job is done, they have begun to fight non-Muslim women who wear shorts and skirts - no longer just in the sensitive Muslim enclaves... where women no longer dare to wear skirts - but now also in the heart of big cities.
According to Berlin police, Chechen Islamists are openly enforcing Sharia law on the city's streets. The self-styled morality police have used threats of violence to dissuade other Muslims from integrating into German society.
The gang, believed to be 100-strong and armed, is linked to Salafist mosques in the capital.
Meanwhile in Wuppertal, a group of vigilante Salafist Muslims wearing hi-vis 'Shariah Police' vests patrolled the streets handing out flyers declaring the city a 'Shariah Controlled Zone' and warning people to abstain from drugs, alcohol, gambling, visiting cafes and listening to music.
The group's ringleader, fundamentalist preacher Sven Lau (below), is a German convert to Islam who was jailed in 2017 for recruiting jihadists.
There have been reports of Sharia patrols also in Hamburg.
Police in The Hague recruited members of a fundamentalist Salafist mosque to keep order one New Year's Eve in the Transvaal and Schilderswijk districts.
They paid them in tourist vouchers.
The stated mission of the Soldiers of Allah is to 'prevent evil and encourage the good' - presumably according to Islamist principles.
Their uniform is a black hoodie decorated with the black flag of ISIS.
According to investigative journalists from TV4, self-appointed morality police have been enforcing 'honour culture' in several suburbs of Stockholm and Nyköping.
The groups are said to have harassed women for wearing skirts, owning dogs or venturing outdoors without a male chaperone.