Legislating for "limited" abortion, a dilemma based on the Sunday Independent opinion poll.

This post is inspired by an opinion poll in last Sunday's Sunday Independent. I can't locate an online version but if anyone can find a link for me I'd appreciate it. 

As I've said before, I ain't no big city lawyer but there's one thing that puzzles me about the reporting in the media regarding the discussion about abortion in the case of rape. There have been opinion polls over the last few weeks that ask people if they favour making abortion available in the case of rape. This is a very emotional question. Rape is a horrible crime, a violation that most of us could never imagine. It is argued that making abortion available in the case of pregnancy arising from rape is a compassionate response to women who have suffered a huge trauma.
I've heard a lot of people who describe themselves as pro-life say that in the case of rape they'd be willing to make an exception, indeed I've heard it from members of my own family. I've heard other impassioned campaigners speak about being forced to carry a reminder of the horrible experience of rape for the rest of their lives.
This is a complicated debate. It attempts to balance the rights of a woman who has suffered a violation and deserves to be treated with compassion and the unborn child. It is an attempt to see justice done, how will that happen? On the other hand there is the new life, does the unborn have any rights in this context? I will not go near any of those questions, instead I have another issue that struck me as I looked at the opinion poll in the Sunday Independent last Sunday (3/2/2013). I can't find a link to an online version but if anyone can please add it in the comment section below. 
If a woman is pregnant as a consequence of rape and seeks an abortion who decides? Since we are discussing a crime, surely it must have to be a judge. A decision to permit an abortion based on the fact that conception occurred as a consequence of rape is a decision that a serious crime has been committed. Will the judge hear evidence on behalf of the accused as in any rape trial? It seems to me that in such a case that would be essential, necessary before any decision could be made.
At this stage I think it's necessary to mention that pregnancy resulting from rape is rare. It is also necessary to mention that most women who are raped are in fact raped by men whom they are in a relationship with. This may be a marriage relationship or an on again/off again relationship. In other words the attacker is known to the victim, it would not be hard to name him to the authorities. The victim may be afraid of her attacker but surely it would be necessary to name him since the decision that a rape took place, and thus an abortion is legal, is a de facto judgement.
Presumably, in the case of limited abortion, there would be a time limit imposed. suppose that limit was twenty weeks. That would leave very little time to carry out an investigation. It is more likely that in the case of limited abortion the accused would have to have his day in court, the right to defend himself. That would be the only right thing to do, however that would lengthen the process to an extent that would make an abortion based on rape impossible. Justice delayed is justice denied but hasty justice does not help anyone either.  
Introducing a limited form of abortion in the very rare case of pregnancy resulting from rape would, in my untrained legal opinion, result in huge legal problems. In order to provide abortion in that very rare case you would have to introduce a very liberal law providing abortion on demand and with no time limit.