"A German court has ruled that a group of Islamists did not break the law in forming “sharia police” street patrols and telling people to stop drinking, gambling and listening to music."
The city’s district court ruled that the seven accused members of the group did not breach a ban on political uniforms when they approached people while wearing orange vests bearing the words “Sharia Police", while claiming they weren't sufficiently "militant of intimidating".-The Guardian
"The vigilantes were led by convert Sven Lau who is simultaneously on trial for backing “a terrorist group” fighting in Syria." - Breitbart
More sharia police were reported in other countries:
"So-called “sharia patrols” by sometimes violent radical young Salafists have also been seen in other European cities such as London, Copenhagen and Hamburg." - The Guardian
"A number of bars in Denmark are reporting daily harassment by migrant sharia patrols" - Breitbart
And here is an exmaple of how this kind of sharia patrol looks like:
Muslim patrol - the truth about saturday night out:
A 15 year old Polish girl living in Austria getting beaten / punished
"What happened was to teach me a lesson. She told the others that I had ripped a woman's headscarf off, and they all flew into a rage." - The comment of a victim.
According to the policeman quote in Heute news website the motive was a dissagreement.
I deduce that it has to do with breaking shariah law since oppresors must have felt justified to act the way they did because they filmed it and only islam would advocate initiation of violence against a girl as a punishment for taking someones headscart off.
https://www.youtube.com/watch?v=6RvuyP4bCl0
Sources:
http://www.breitbart.com/london/2016/11/22/german-court-says-islamic-sharia-patrol-legal/
http://www.breitbart.com/london/2016/05/13/bar-owners-appeal-police-protection-sharia-patrols-smash-premises-announce-alcohol-ban/
https://www.theguardian.com/world/2016/nov/21/germany-sharia-police-court-ruling
http://www.thelocal.at/20161115/teen-victim-speaks-out-after-shocking-video-of-beating
https://translate.google.com/translate?hl=en&sl=auto&tl=en&u=http%3A%2F%2Fwww.heute.at%2Fnews%2Foesterreich%2Fwien%2Fchronik%2FWarum-Pruegel-Opfer-Patricia-17-sich-nicht-wehrte%3Bart85950%2C1368611
https://kurier.at/chronik/wien/jugendliche-schlugen-auf-maedchen-ein-und-stellten-video-ins-netz/230.491.268( sorry for not posting english translation - translator refused to cooperate )
https://www.youtube.com/watch?v=WslaoxH6MIA ~ 9:45