Can't theoretically a man walk around in a Burka pretending to be a woman while passing CCTV on the way to commiting a crime, because walking round the side of a his ex's building where he planned to murder her in a balaclava would look rather suspicious the next day when she's found murdered and they check the CCTV, however with a burka on you can be actively hiding your identity but without arousing suspicion that thats exactly what you're trying to do.
Meh, even so I don't think it should be banned, because then we'd be wanting to ban, poncho's, or have every gps tagged so no matter what you were wearing the police would know where you are.
You CAN'T treat everyone like they might commit a crime and you can't change what people are allowed to do incase they commit a crime. Criminals should lose certain rights to protect the rest, but people who have done nothing should be free to do and wear what they want.
I think its entirely up to a premises own personal choice if they require anyone coming in to pay for say, petrol, to not be covering their face for safety reasons, if they want to lose business thats fine.
However there really should be a reason, IE if they've had 4 holdup's by motobike riders who have kept their helmet on, you'd understand them requesting them to take their helmets off, but randomly deciding all Burka wearers are a large risk is a rather large jump to make.
Same way places that have trouble with hoody wearers are understandly worried by groups of hoody wearing chavs, but its ridiculous when there was that case of a 70yr old woman being asked to take the hood off from the jacket she was wearing while around a Tesco's, or something along those lines.
Common sense + a little respect for everyones right to wear what they want added to everyones right to refuse service to people for any reason, especially if they are genuinely worried would go a long way.
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) than if you've come from 10 or 20 generations of family living in the UK alone.