[7] Lyons was described by one of the gardaí (policemen) involved in the case as a "Walter Mitty" character,[8] and Charles Smith, psychiatrist and director of the Central Mental Hospital, Dundrum, felt that he might be prone to exaggeration and attention seeking.

[12] On the morning of 7 March 1997, Sylvia Sheils and Mary Callinan were found dead in No.1 Orchard View, Grangegorman, Dublin, having been stabbed a number of times.

The address was a two-story end of terrace house owned by the Eastern Health Board and was used to provide sheltered accommodation for outpatients of St Brendan's Psychiatric Hospital.

The entire Orchard View area was completely demolished fifteen years after the murders and is now an empty plot surrounded by a wall.

[13][14] The killings were described as "the most brutal murders in Irish criminal history" by the Irish Examiner newspaper[15] After the alarm had been raised, a major investigation commenced involving detectives from the Dublin Metropolitan North Central Division and the National Bureau of Criminal Investigation (NBCI).

A postmortem examination of the bodies was made by the State Pathologist, Professor John Harbison; his first report was delivered on 13 March 1997.

Among other items in their initial report, they said that "THE OFFENDER WAS EXTREMELY DANGEROUS AND WAS LIKELY TO REOFFEND" (emphasis in original), and that the killer was likely to have had prior experience of burglary.

A local resident had noticed someone acting suspiciously a week or two before the killings; his statement to the Garda was used to make a facial composite:[16] "I would describe this fellow as about 6-foot to 6-foot 2, aged 35 to 38 years, very slim, had a black moustache, long at the side.

"[16]As a result of the psychological profile, the Garda broadcast an appeal for information on the RTÉ television programme Crimeline with a request for people whose houses had been broken into in the Grangegorman area to contact them.

During the interview, he was confused about the number of people that had been killed, and he thought that the women were awake, and moving about the house at the time, which conflicted with the forensic evidence.

Gísli Guðjónsson, a psychologist engaged by Lyons' solicitors, found that he was very suggestible and susceptible to leading questions.

DL: "It was the second room from the top of the stairs and she was stout about one or two inches smaller than me and she had grey shoulder length hair.

[1][25] During his interview with the gardaí, he said that about three months prior to his arrest, as he was walking to Stoneybatter, he broke into a house through the back, and had stabbed two women in their sleep.

[1] Nash's confession caused some consternation amongst the gardaí, as Dean Lyons had been charged at that point and was on remand awaiting trial.

[27] As a result of Assistant Commissioner McHugh's investigation and due to the defence solicitor's refusal to release Gísli's report, the Director of Public Prosecutions' office appointed a psychologist, Adrian Grounds, to assess Dean Lyons.

However Mr Lyons' account to me in our interview supported and was consistent with the earlier impressions I had gained from reading the case papers.

Following my interview with Dean Lyons and his parents, these concerns are substantially strengthened and I now think that it is very likely that his detailed admissions were unreliable.

"As a result of Grounds' report, the charge of murder against Dean Lyons was dropped on 29 April 1998; he had been imprisoned on remand for nine months.

23 of 2004) on the following specific matters:1) the circumstances surrounding the making of a confession by Dean Lyons (deceased) about the deaths of Ms Mary Callinan and Ms Sylvia Sheils in March 1997 in Grangegorman Dublin 7,2) the adequacy of the Garda assessment of the reliability of Mr Lyons' confession both before and after he was charged with murder, and 3) the adequacy of information provided by the Garda Síochána on the morning of 27 July 1997 to the Director of Public Prosecutions and in particular whether any additional information should have been provided at that time.

McNulty was one of the detectives who interviewed Dean Lyons after he made his initial confession; he received a suspended jail sentence of twelve months and a €5000 fine for leaking the report.

The commission found that: "The written record maintained of the non-video-recorded interviews is not comprehensive and matters are excluded that would have assisted in the assessment of the reliability of Dean Lyons.

This is not in accordance with section 12 (11) (b)(i) of the Criminal Justice Act (Treatment of Persons in Custody in Garda Síochána Stations) Regulations 1987."

The report said that Dean Lyons was not abused or ill-treated during his detention and that: His admissions were not produced by oppression or coercive conduct on the part of the Gardaí.

However, Dean Lyons was able to provide accurate details of murders it is now accepted that he did not commit, due to the manner in which he was interviewed by gardaí.

[35] In July 1998 the Garda recommended charging him for the Grangegorman murders, and in September 1999 the Director of Public Prosecutions (DPP) said this should be done when the Book of Evidence was complete.

[37] As Nash was already in prison, the urgency was less, and pressure of other work meant the Forensic Science Laboratory was slow to test items of evidence.

[40] He launched a legal challenge, claiming excessive delay and negative publicity would prevent a fair trial.