Timeline: The Grangegorman murders... 18 years later Nash is found guilty
Just over eighteen years after the discovery of the bodies of Mary Callanan (61) and Sylvia Shiels (60) at Grangegorman, Mark Nash is found guilty of the double murder. Here is a brief timeline of the events leading up to the jury's 'guilty' verdict.
March 7, 1997
Mary Callanan (61) and Sylvia Sheils (60) are found dead in sheltered accommodation at Grangegorman. The women suffered horrific and multiple fatal injuries with a carving fork and other implements.
July 26, 1997
Dean Lyons admits to both the killings during garda questioning.
July 27, 1997
Dean Lyons is charged with the murder of Ms Callanan. It is expected he will be charged at a later date for Ms Sheils’ death.
August 16, 1997
Mark Nash (24 years of age at the time) is taken into custody for the murders of Catherine Doyle (28) and her husband Carl (29) in Castlerea, Co Roscommon.
He also seriously injured his girlfriend and Catherine’s sister, Sarah Jane Doyle (19 years of age at the time). A garda sergeant discovered a seven-year-old boy and two crying babies at the scene.
During questioning, Mark Nash admits to the Grangegorman double murder in March of the same year. He gives the gardai information that had not been published in the media.
Mark Nash formally withdraws his admission in a series of verbal and written communications with gardai.
A Garda report of the two admissions is established but it is unable to define which man’s admission is the truth.
Another Garda report strongly questions Dean Lyons’ admissions. The charges against him are dropped.
Dean Lyons dies a short while after he is released from prison in Manchester.
Major advances in DNA technology raised garda investigators' hopes that they would ultimately be able to provide sufficient evidence to substantiate charges. Fresh tests are carried out on materials retrieved from the scene of the horrific crimes.
Two years after the death of Dean Lyons, a Garda working group is established.
Gardai formally apologise to the Lyons family.
Detectives investigating the murders send more forensic samples taken from a window sill in the kitchen of the house where Mary Callanan and Sylvia Shiels had lived.
A Commission of Investigation is established, following the then Justice Minister Michael McDowell’s suggestion that there was no need for an inquiry.
Mark Nash, serving life for the Doyle killings, is charged with the Grangegorman murders.
Mark Nash fails in a High Court bid to restrain the Director of Public Prosecutions from charging him with the double murder.
Mark Nash goes on trial for the Grangegorman murders.
April 20, 2015
Mark Nash is found guilty of murdering Mary Callanan and Sylvia Shiels.