Comments made by an Irish woman who is being held in a Syrian refugee camp saying she just "ran with the crowd" are being questioned by retired Lieutenant Colonel and former deputy director of military intelligence, Michael Murphy.
Lisa Smith made the comments in an interview with The Irish Mail on Sunday in which she said she wants to come home.
It is understood Ms Smith, who is originally from Dundalk in Co Louth, travelled to Syria three years ago and now has a two-year-old child.
She is now being held at the Al Hawl refugee camp on the Syrian border with Iraq.
Ms Smith has previously served as a Private in the Irish Defence Forces, having joined at 19 years old.
She also served in the Air Corps, working for a time on the Government jet.
In an interview with The Irish Mail on Sunday, Ms Smith denied fighting for so-called Islamic State or ever owning or using a gun while there.
The Irish Mail on Sunday reported that Ms Smith confirmed she married a British man while in Syria and she said he died in the past three months.
Mr Murphy said the Government needs to find out who the people that Ms Smith was associating with were.
"Who are 'the crowd', where was that crowd, are there other people in Ireland that left at the same time, or did she leave individually at that time?"
Speaking on RTÉ's Morning Ireland, he said it is like somebody who did something wrong is trying to get out of it, and it would be very difficult to prove what they did wrong.
Mr Murphy said the Government failed to bring in proper laws in Ireland to make it illegal for someone to travel to IS territory. Therefore, he added, the State can do nothing to prosecute someone if they have conducted illegal acts in places like Syria.
He said there should be no reason for an Irish citizen not to be able to return home if they still have their passport.
However, he questioned whether Ms Smith handed her Irish passport over to IS and became a citizen of the caliphate.
"When the Government says they're going to carry out a threat assessment - the threat assessment should be carried out before anybody comes back into this country, not afterwards - that's a bit late."
Mr Murphy said a European Directive in 2017 recommended that travelling to IS territories should be made a crime, but the Government never went down that road.
He said in the UK people are convicted and imprisoned for wanting to travel to an IS territory, but that there is no such law in Ireland.
As a result of what he sees as a lack of legal procedures, he believes someone like Ms Smith will not be prosecuted.
"It's probably that she will be interviewed by the gardaí and unless she says something incriminating against herself, its unlikely anything will happen and she'll be released on to our streets, as will anybody else who might come back. Then they have to be kept under surveillance."
He said this type of surveillance would be necessary to keep Irish citizens safe and would possibly be needed for the rest of her life.
"To keep somebody under surveillance properly, its a 24-hour job, seven days a week, every day of the year."
However, Mr Murphy does not think the Government should waste taxpayers' money bringing Ms Smith home from Syria. He said she got there by her own volition and should make her own way back.
He said there is a difference between being allowed home and being brought home. He acknowledged that it is a harder case given that there is a child involved.