It is an issue which has polarised opinion, caused heated debates and been discussed by top levels of government.

But hard facts on Muslim women’s dress – be it the hijab, burka or niqab – are harder to come by.

As Channel 4 News continues with its series on Britain’s Niqab, FactCheck digs deep to see whether the figures back up the pronouncements.

The claim

“The number of women wearing the burka and niqab has exploded in Britain in recent decades”.
– Anne Marie Waters, council member of the National Secular Society, August 2012

The verdict

Verifying how many Muslim women wear the niqab, or burka, is notoriously difficut, not least because definitions of what the garment is seem to vary.

We’ve asked the Muslim Council of Britain, the Muslim Women’s Network, and the group Faith Matters whether they had any figures on this, and all agreed the numbers are unlikely to exist.

A study in France in 2009 by the internal security services suggested that out of a population of 1.5 million to 2 milllion adult Muslim women, about 1,900 wore either burkas (defined here as a full-body and head covering) or niqabs (where the eyes can be seen).

This figure of 1,900, however, came because the secret service initially came up with a figure of 367, which was deemed to be so low they were asked to count again.

To be fair to the Anne Marie Waters, she isn’t the only one suggesting increasing numbers of women are wearing the garment.

What we do know, however, is that the number of Muslim women and girls living in the UK has risen in the last decade.

In the 2001 census, there were 748,000 women who gave their religion as Muslim, and this had risen to 1.3m by 2011 – an increase of 74 per cent.

If the percentage of Muslim women wearing niqabs or burkas has remained constant, there will have been a rise in the overall number who wear burkas or niqabs, as the population has increased by quite an amount.

What we don’t know, however, is whether more Muslim women are wearing it than previously. In order to do that, we’d need to know the proportion of Muslim women wearing the veil to begin with, compared with the number who do now.

The claim

“There’s overwhelming support for banning the veil. People feel it’s alien to our way of life.”
– Philip Hollobone MP, 19 September 2013

To ban or not to ban has been the question on the airwaves in recent weeks.

A ComRes/Channel 4 News poll showed that more than half of the public believe women should not be allowed to wear the niqab in public – with 55 per cent backing an outright ban similar to the one in France.

An even greater proportion, 81 per cent, say they support a ban on wearing the niqab in certain public places, such as schools, courts or hospitals.

Last month, a poll for YouGov for The Sun newspaper suggested that 61 per cent of people supported a ban on burkas – defined as a “loose garment worn by women in some Islamic traditions for the purpose of hiding a female’s body and face when out in public”.

But less people now support a ban than previously.

When asked “The burka should be banned in Britain”, 27 per cent disagreed in April 2011 (66 per cent agreed it should be banned), and that had risen to 32 per cent in September (with 61 per cent agreeing).

The claim

“The niqab … collude[s] with making women invisible.”
– Dr Sarah Wollaston MP for Totnes, 16 September 2013

Writing on Twitter, Dr Sarah Wollaston repeated her position that the niqab makes women “invisible”.

She may be speaking metaphorically, but it’s ironic, given that perpetrators of hate crimes against Muslim women appear to have specifically targeted them because of the visibility of the garment they’re wearing.

Figures collected by the group Tell MAMA, which measures attacks against Muslims, suggest that the majority of Muslims who have been physically attacked, or harassed or intimidated because of their faith are women.

The helpline logged more than 630 incidents during the first 12 months of its existence, and Muslim women were targeted in 58 per cent of all incidents.

Tell MAMA has been able to give a breakdown of the nature of the incidents reported. Some Muslim women have called because they have been forced to remove their veil in public buildings, for example the Home Office.

However, several of the other incidents were directly targeted at the veil itself – for example having it ripped off, having faeces smeared on it, or being told “take that ****ing thing off”.

In July, the group released a report which suggested that over 80 per cent of abusive attacks against Muslim women – in ‘offline’ attacks, as opposed to online – the women were wearing the hijab or niqab.

What we don’t know, however, is the religious profile of victims of sexual violence. The Crime Survey for England and Wales doesn’t ask this specific question, and there appears to be little other information as an alternative.

So, while some women may feel the niqab protects them from sexual advances by men, research suggests it could also make them a greater target on the street.

Dr Chris Allen, of the University of Birmingham, wrote the report, Understanding the Impact of anti-Muslim Hate on Muslim Women, and the report is due to be published next month.

He said: “As well as the symbolic value of the garment, the garment itself can be the target of hatred. If you’re the sort of person who perpetrates hate crimes, it becomes very easy to target the person [wearing the niqab].

“There is a stereotype of [women wearing the niqab] as oppressed and meek, and if you want to attack them, it makes them appear an easier target.”

So while Dr Wollaston may consider women who wear the niqab as “invisible”, their attackers do not.