Gerry Adams will not face prosecution for allegedly withholding information relating to the rape and sexual abuse of his niece Aine by his brother Liam.
While a report published today by the North's Attorney General states that there was "sufficient information" the Sinn Fein President was aware of the nature of the allegations made against his brother Liam to merit further investigation of that issue, the report found that the public interest was better served by using Mr Adams as a witness in the subsequent trial.
Attorney General John Larkin QC said: "It should be open to the PPS to make a public interest decision that such persons should be treated as witnesses and not treated as suspects by the PSNI or prosecuted without first having to take all those steps necessary in order to ascertain whether the evidential test is or is not satisfied."
The report also found that the PPS did not follow the “normal procedures” which would ordinarily have applied in such a case.
"The PPS did not follow the normal procedures which usually apply in a case in which the need to give consideration to prosecuting an additional suspect arises in the context of an existing file," the report says.
"While the role of the PPS is not to investigate crime, I consider there was sufficient information regarding Gerry Adams's state of knowledge to at least merit obtaining a further statement from Aine Dalhstrom concerning the issue of what she had told her uncle.
There was certainly some evidence on the police file that indicated knowledge on the part of of Gerry Adams that the abuse perpetrated against his niece amounted to rape or unlawful carnal knowledge and no action was take to clarify the issue," it adds.
Liam Adams was convicted in 2013 for the abuse and rape of his daughter, Aine Dahlstrom, in the 1970s.
Gerry Adams confronted his brother in 2000 but did not report his knowledge to police until 2007.
Prosecutors took a decision to call Gerry Adams as a witness in his brother's trial when the allegations finally came before the courts.
But after Liam Adams was convicted, the North's Attorney General John Larkin was tasked with investigating the decision-making process deployed by the prosecution service.
It is stated in the report that Ms Dahlstrom does not want to pursue the matter further.
“Accordingly, we have concluded that there is insufficient evidence to meet the test for prosecution in this case,” added deputy Director of Public Prosceuctions Pamela Atchison.
The report, published this afternoon, states that the PPS should have sought further clarity surrounding Mr Adams's knowledge of the abuse by his brother.
It refers to an interview given to police by Ms Dahlstrom in 2006.
The report states that following the interview, it was "clear that Aine had told Gerry Adams what her father had done to her".
"Furthermore she told police specifically that her mother and Gerry Adams were present when she accused Liam Adams of 'putting his thing in me'."
The report states that the authors were not tasked with determining whether Mr Adams should have, or should be, prosecuted for allegedly with holding information.
Central the the case at the hand was the decision making process surrounding two legal tests applied in the case - the evidential test and the public interest test.
The evidential test was applied first, and correctly so according to the report, but it was decided that it was not met in the case of Gerry Adams.
"The decision that the evidential test had not been met was ‘perhaps premature’ in circumstances where the evidence on the file was unclear as to the extent of Gerry Adams’ knowledge of the nature of the sexual abuse. Any doubt as to whether the evidential test was or was not met could have been resolved by inviting clarification from the principal witness."
The code followed by the PPS requires that the evidential test be "passed before the public interest test be considered".
Nonetheless, the report states, the PPS went on to consider the public interest element and decided to use Mr Adams as a witness for the prosecution.
In a statement today, Mr Adams said he welcomed “the conclusion of the PPS that I should not be prosecuted for an offence of withholding information. I committed no offence.”
“I want to welcome the publication of the Attorney General report.
“This report underlines the trauma that allegations of abuse engender within families; the importance of every possible help and support being provided for victims and families; and the legal difficulties that surround such cases, particularly in respect of creating an atmosphere in which witnesses will come forward.
“I hope that this report will assist state agencies, including the police, judiciary and prosecution authorities, in dealing with cases of alleged sexual abuse.
“I have consistently maintained that my sole interest was in helping and supporting Áine and that in these endeavours I did nothing wrong.
“This has been a very difficult time for Áine, her family and the wider Adams family.
“I welcome the conclusion of the PPS that I should not be prosecuted for an offence of withholding. I committed no offence.”