Nicola Sturgeon has been unable to say whether a transgender sexual offender is a man or a woman as she was accused of “giving rapists an easy way out”.

But the First Minister suggested that it is “almost certainly the case” that a double rapist is not truly transgender.

The Scottish Government has come under pressure from opponents after it emerged a transgender double rapist was being held in a female prison, albeit in isolation.

Another report emerged of another transgender sexual offender bidding to be moved to a female jail.

Read more: Keith Brown urged to reveal SNP involvement over transgender prisoners

Isla Bryson was initially taken to Cornton Vale prison near Stirling – Scotland’s only all-female jail – after being convicted, before being moved to the male estate following public outcry.

Scottish Conservative leader Douglas Ross used First Minister’s Questions on Thursday to try and corner Ms Sturgeon on her belief in self-ID – the process by which a trans person does not require a medical diagnosis to identify as a gender different to that of their birth sex.

Ms Sturgeon said she does not know if Bryson is lying.

The First Minister was asked whether Bryson was a man or a woman, but claimed she “does not have enough information”.

Ms Sturgeon said: “I think that rapist should be considered a rapist. That’s what I think.

“That individual has been convicted of rapes and that therefore is the terminology. I’m not going to get into the individual circumstances of that particular individual’s claims to be a woman because I don’t have enough information about that.”

She added: “This individual claims to be a woman. What I said is that I don’t have information about whether those claims have validity or not.

Read more: 

"But I don’t think Douglas Ross and I are disagreeing here, because what I think is relevant in this case is not whether the individual is a man, or claims to be a woman or trans, what is relevant is the individual is a rapist.

"That is how the individual should be described, and it is that that should be the main consideration in deciding how the individual is dealt with.

“That is why, of course, the individual is in a male prison, not in a female prison. There are the issues that matter.”

Mr Ross pointed to the “current Scottish Government policy” which states “the view of the Scottish Government that trans women are women”.

He added: "It is the view of her justice secretary that a double rapist is a woman.

“I’m not sure what the First Minister’s view on that is, because she says there’s no disagreement between herself and I on this.

"There is a massive disagreement. I believe a double rapist, anyone who rapes a woman, is a man. They cannot be considered anything else.

"This all matters for very good reasons. It matters because what happens when violent criminals like Adam Graham get out of prison.”

Read more: Keith Brown was not aware trans rapist being held in female jail

Mr Ross read a statement from one of the victims of Bryson, formerly known as Adam Graham, which said: “I’m sure he’s faking it…You’ve got genuine cases where people are desperate to get a reassignment for the right reasons because they have been born into that body – not because they raped two people and decided that that is an easy way out”.

Mr Ross accused the First Minister of “giving rapists an easy way out”.

But Ms Sturgeon said the accusation “does a disservice to victims of crime”.

Responding, the First Minister said: “The quote that Douglas Ross narrated there, my feeling is that is almost certainly the case, which is why the key factor in this case is not the individual’s claim to be a woman.

“The key and only important factor in this is that the individual is convicted of rape – the individual is a rapist – and that is the factor that should be the deciding one about the decisions about how that prisoner is now treated.”

Read more: Nicola Sturgeon urged to clear up trans prisoners 'chaos'

Ms Sturgeon went on to say it is “really important” to “look seriously” at the issues thrown up by the Bryson case, adding: “But that in doing so, we bear in mind two things.

“Firstly, as I’ve said, that we do not further stigmatise trans people generally – I think that is important – but secondly that we don’t cause undue concern amongst the public.

“If there are issues to be addressed we address them, but we do that in a way that’s not just calm, but doesn’t misrepresent the situation, because that is in nobody’s interest.”