A Co Armagh man sentenced for the murder of garda officer Adrian Donohoe has begun an appeal against his conviction.
Aaron Brady, of New Road in Crossmaglen, was sentenced to life with a 40-year minimum term following the conviction in 2020.
His trial was the longest-running murder case in Irish legal history.
Detective Garda Donohoe was shot dead in January 2013 in Bellurgan, Co Louth, while on duty as a cash escort at Lordship Credit Union.
The 41-year-old officer was ambushed by a five-man gang who fled the scene with €7,000 in cash.
Brady, who denied involvement in the robbery, has claimed his trial was unfair as it took place during the Covid-19 pandemic.
Representing Brady, senior counsel Michael O'Higgins told the Court of Appeal the jury in the trial should not have been working at the time as the pandemic meant there was a "real threat to their existence".
He said concerns over their safety due to Covid likely "deteriorated the quality of their decision" and that it was wrong for the trial judge to direct the proceedings to continue.
Senior counsel for the state, Brendan Grehan, described Brady's application as "highly speculative" and that there was "not an iota of evidence" the jury felt compelled to serve.
He said the jury "made it sufficiently clear they were happy to proceed".
The hearing was told the appeal would also be grounded on defence complaints regarding other witnesses.
The case is expected to continue until early next week.
