A judge has refused to allow a Muslim woman to stand trial in a full-length burqa as he said it would be possible for another person to enter the dock pretending to be her.

Judge Peter Murphy told the 21-year-old defendant from Hackney in east London that he would not allow her to enter a plea in court until she showed her face.

The woman, who is facing an allegation of intimidating a witness in Finsbury Park in June, told Blackfriars crown court she could not remove the veil in front of any men because of her religion.

The judge said the principle of open justice overrode the woman's religious beliefs. "It is necessary for this court to be satisfied that they can recognise the defendant," the judge said.

"While I obviously respect the right to dress in any way she wishes, certainly while outside the court, the interests of justice are paramount. I can't, as a circuit judge, accept a plea from a person whose identity I am unable to ascertain.

"It would be easy for someone on a later occasion to appear and claim to be the defendant. The court would have no way to check on that."

Claire Burtwistle, the woman's barrister, told the court the woman was not prepared to lower her veil at all while men were in the room. The woman cannot be named for legal reasons.

"In front of women, it is not an issue. It is simply men that she will not allow to see her face," the barrister said.

Burtwistle suggested that she, a female police officer or a female prison guard could identify the defendant and confirm to the court that it was the same person as in the police arrest photos.

Sarah Counsell, prosecuting, said the police officer in charge of the case was content that he recognised the defendant while she was in the burqa.

But the judge said: "It seems to me to be quite fundamental that the court is sure who it is dealing with. Furthermore, this court, as long as I am sitting, has the highest respect for any religious tradition a person has.

"In my courtroom also, this sometimes conflicts with the interests of a paramount need for the administration of justice. In my courtroom, that's going to come first.

"There is the principle of open justice and it can't be subject to the religion of the defendant whether the principle is observed or not.

"I am not saying this because of the particular form of dress by this defendant, I apply that to any form of dress that had the same issues."

The case was adjourned for legal argument over whether or not the defendant should have to remove her veil. It will be heard again on 12 September when the defendant is expected to enter a not guilty plea and go to trial.