There are lessons in the Wall case, writes Carol Coulter, Legal Affairs Correspondent
Nora Wall received the maximum sentence for rape in 1999, when Mr Justice Paul Carney sentenced her to life imprisonment for the rape of Regina Walsh.
He described it as a "gang rape" and she was convicted following evidence that she had held the then 10-year-old girl down while she was raped by a homeless man, Paul McCabe. We now know that evidence to be false. Mr McCabe, who is now dead, was sentenced to 12 years imprisonment.
Ms Wall ran St Michael's Child Care Centre in Cappoquin, Co Waterford, and Mr McCabe was a frequent visitor. He suffered from mental illness, alcoholism and Parkinson's Disease. He had been in care in Artane boys industrial school until the age of 16, and had spent six months in the Army. He could have been regarded as a vulnerable witness. He had convictions for larceny, assault and sexual assault.
Regina Walsh and Patricia Phelan were among the children who came to the centre in Cappoquin. Both came from troubled backgrounds. Ms Walsh went on to spend time in a mental hospital.
It has also emerged that both girls made multiple allegations of sexual assault against a variety of people, both inside and outside their families. No one was charged in relation to any of these allegations; at a judicial review challenging one of them, Mr Justice Brian McCracken described Ms Phelan's evidence as unreliable.
However, shortly after leaving the childcare centre at the age of 18, when Regina Walsh made her allegations against Paul McCabe and Nora Wall, most of this was yet to come.
Ms Walsh asked Patricia Phelan to back her up and she agreed. She described what she claimed happened and, in a later statement to gardaí Ms Phelan repeated it, embellishing the story "to make it more real", by describing how she had cleaned Ms Walsh up and changed her sheets.
The case was due to start in 1998, but Ms Walsh could not be found. It eventually opened early in June 1999.
It took place at a time of heightened sensitivity to the problem of the sexual abuse of children in institutions, especially those run by religious orders. The RTÉ series States of Fear had ended a month earlier, generating widespread debate and indignation.
During the trial, the jury was warned of the danger of convicting a person on the basis of an allegation without corroboration. Ms Phelan's evidence was crucial corroboration; it is significant that the jury did not convict on charges of other instances of rape which she did not corroborate.
It was acknowledged by the DPP in 1999 that Ms Phelan should not have been called as a witness.
There was also, however, other claimed corroborative evidence, that of Mr McCabe. He had made three statements to gardaí admitting rape and implicating Ms Wall. His statements admitted to a rape in 1990 and another rape, allegedly between 1987 and 1989, was added to the indictment. He made no statement relating to this. No notes were taken of the interviews and there was no record of the questions put to him. His defence team contested these statements in court.
When he and Ms Wall were convicted, it was on the rape allegedly before 1989 (for which there was no statement), not the 1990 one (for which there was a statement). Ms Phelan claimed to have witnessed the earlier alleged rape.
Mr McCabe is now dead and cannot be asked how he came to make these statements.
The DPP has said he and Ms Wall are both fully entitled to the presumption of innocence with regard to this crime.
There are uncanny echoes of the Dean Lyons affair, where a homeless drug addict confessed to murdering two women in a house in the grounds of Grangegorman psychiatric hospital in 1997.
This is now being examined by a commission of investigation headed by George Birmingham SC, who will examine the way in which vulnerable witnesses are dealt with by gardaí as part of it, and will make recommendations.
It is clear from the whole sorry saga concerning Nora Wall that vulnerable people can make false allegations and indeed confess to crimes they did not commit.
While in normal circumstances confessions might be viewed with some scepticism by juries, generally claims of child sexual abuse are not. This is all the more so in an context where members of religious orders were shown to be capable of terrible abuse, and some people tarred all their members with the same brush.
It is now clear how vital it is to be able to challenge all such evidence. When politicians and commentators complain about the allegedly excessive rights enjoyed by the accused, they would do well to remember Nora Wall.