The Oireachtas committee examining the Eighth Amendment has been advised that if a woman is granted an abortion because of an alleged rape, this may have to be disclosed in a criminal trial.
Tom O'Malley, law lecturer at NUI Galway, told the committee members it would be very difficult to legislate to allow for terminations in cases of rape.
A number of policy decisions would be required, including who would validate the claim of sexual assault and what level of proof would be required.
Mr O’Malley recommended a panel could be established to make a determination but stressed this was a policy decision for Government.
Another consideration would be whether a termination would have to be disclosed during proceedings against the alleged perpetrator.
In response to a question by Social Democrats TD Catherine Murphy, Mr O'Malley said there was a constitutional protection for the accused and this may become an issue if the Oireachtas decided on this course of action.
The committee was advised by Mr O'Malley that such difficulties would be avoided if abortion were made available up to 12 weeks in Ireland.
If a verification process were required, he said, women may still be forced to travel to the UK to avoid the trauma of having to prove a rape.
Independents4Change TD Clare Daly said Mr O'Malley's evidence demonstrated there was "no chance in hell" legislation could be provided in rape cases.
In response, Mr O’Malley said it could be done but it would be legally complex and therefore open to legal challenge.
10,000 lives
Noeleen Blackwell, chief executive of the Dublin Rape Crisis Centre, also told the committee there was no reliable information about the prevalence of pregnancy as a result of rape due to the under-reporting of sexual assault.
However, based on its own figures, 4 per cent of the women who used their services reported pregnancies as a result of rape.
Ms Blackwell advised members many women who have been raped were unwilling to report to gardaí for a "long time, if ever".
Requiring a woman to share her experience about her rape had the potential to retraumatise, retrigger and revictimise her, she added.
Earlier, Prof Veronica O’Keane said Ireland’s restrictive abortion regime was damaging the mental health of all Irish citizens, not just pregnant women.
Fine Gael TD Peter Fitzpatrick put it to Prof O'Keane that the pro-choice side was trying to prove abortion was a good thing for women and did not damage their mental health. He said there was evidence abortion had an adverse affect on a woman's mental health.
Ms O’Keane told him he was “misinformed” and offered to send him more information.
Mr Fitzpatrick also put it to her that 100,000 lives had been saved by the Eighth Amendment, to which she responded: "I'm baffled, I don't understand that statistic, I haven't met anyone who's been able to explain that to me."