Mark Nash pleads not guilty to 1997 murders

This report is a localnews.ie summary based on public court reporting and records; sources are listed below.

Mark Nash, 42, has pleaded not guilty at the Central Criminal Court to murdering Sylvia Shields, 60, and Mary Callanan, 61. The charges concern murders alleged to have occurred between 6 and 7 March 1997. The proceedings were reported on 6 March 2015.

The court had heard evidence that Mark Nash wore a black pin-striped velvet jacket at a charity quiz at the GPO on O’Connell Street on 6 March 1997. Brendan Grehan SC, opening the prosecution’s case, had told the court that new tests in July 2009 found DNA belonging to Sylvia Shields and Mary Callanan on the jacket.

Forensic scientist Matthew Greenhalgh told the court that his colleague swabbed the first button during testing in 1998, but no DNA profile was obtained. The court heard that he had been instructed to concentrate on that button and stop if it yielded no result. Matthew Greenhalgh said the other buttons and threads were therefore not examined.

Matthew Greenhalgh said the short tandem repeat technique used had been superseded since 2000. The trial was continuing.