A murder suspect, who hanged himself soon after a court appearance, had not been checked by staff for almost an hour although he had been on suicide watch.
A report into the death of Shane Rogers more than a year ago identified a lack of communication within the prison system as a "deficiency" that needed to be resolved.
Mr Rogers (32), from Deery Terrace, Inniskeen, Co Monaghan, had been charged with the murder of Armagh GAA footballer James Hughes when he took his own life shortly after appearing at Cloverhill District Court on December 20, 2011.
He died as a result of hanging.
The inspector of prisons, Judge Michael Reilly, was asked to inquire into the circumstances surrounding his death.
In his report, published yesterday, Judge Reilly found that relevant information in the possession of prison authorities at Cloverhill prison had not been shared with staff tasked with escorting the man to the courthouse and detaining him there.
Orders had been given to check on vulnerable prisoners every 15 minutes but Mr Rogers was not checked from 12.03pm until 12.58pm when he was discovered in the holding cell by officers and the alarm was raised.
The report also highlighted a failure to adhere to stated work practices and comply with standard operating procedures and inadequate record keeping.
Judge Reilly found that the medical staff, the governor and his officers acted properly and responsibly prior to Mr Rogers' transfer to court that day.
Justice Minister Alan Shatter said last night he hoped the report, which had identified some system failures, would help to clarify matters for all affected by this tragic case, particularly the families of Shane Rogers and James Hughes.
He said the report was being taken very seriously by the Irish Prison Service and director general Michael Donnellan had put an action plan in place to implement recommendations.
Measures were being introduced to ensure that operating procedures and orders given by governors and chief officers were implemented and all staff were being reminded of their obligations and duties, he added.
Mr Rogers had regarded Mr Hughes as a love rival.
Mr Hughes was hit by two blasts from a double-barrelled shotgun as he was dropping a female friend home after a night out. He had been sitting in a taxi with his friend at the time.
Mr Rogers had previously been in a relationship with the woman.