A lawyer for a convicted child killer has accused police of botching the disclosure of papers to the inquest of another missing schoolgirl.
Robert Howard is set to be a witness at the long-delayed coroner's court inquiry into the disappearance of Arlene Arkinson in 1994.
Fifteen-year-old Arlene, from Castlederg, Co Tyrone, vanished after a night out at a disco across the Irish border in Co Donegal.
Eleven years later Howard, who was the last person seen with her, was acquitted of her murder. The trial jury was unaware of his history of sex attacks and his conviction for strangling south London teenager Hannah Williams in 2001.
With no body ever found, lawyers for 69-year-old Howard, who is serving a life sentence at HMP Frankland in Co Durham, intend to challenge the presumption Arlene is dead when the inquest gets under way next September.
At a preliminary hearing today before Northern Ireland's senior coroner John Leckey in Belfast, the killer's barrister Karen Quinlivan QC heavily criticised the police's handling of disclosing papers to the court.
Her criticism centred on how and why officers blanked out large sections of the documents on privacy grounds - rendering them, in her opinion, useless for the purposes of the hearing.
On the foot of previous concerns raised by Ms Quinlivan, police had been requested by the court to provide explanations as to why certain redactions had been made.
The barrister reacted with incredulity today when a lawyer for the police conceded that no such explanation could be provided because officers conducting the exercise had not noted down their rationale for blanking out text when they were doing it.
"One assumes that somebody when they were going through it with a black marker took a note why they did that," she said.
"It seems extraordinary that a person who was engaged in the exercise in the first place didn't record why those redactions were made."
Mark Robinson, representing the PSNI, said officers were now reviewing all the documents again.
He explained that the error occurred because, in a bid to expedite disclosure, the redactions had been undertaken by officers from the PSNI's Major Investigation Team (MIT), rather than the under-pressure police personnel that usually deal with the process.
"MIT took it upon themselves to redact the papers to move matters forward," he told Mr Leckey.
"They are murder investigators, not redactors, and that resulted in no schedule as to why matters were redacted."
Mr Robinson added: "I can understand the frustration in this case but difficulties have arisen and the police are doing their very best to resolve the issues."
Ms Quinlivan accused the police of wasting public resources.
She insisted there was no need to fully reassess the redactions - as the ultimate decision on what would be blanked out would be taken by the coroner - and said the police should instead just focus on finding out the reasons why they were made.
"Police are literally creating work for themselves on an exercise they have already messed up once," she said.
"This is a waste of public resources. At a time when the chief constable (George Hamilton) is complaining about resources he is getting his officers to do their homework again."
During this morning's hearing, particular focus was placed on the police's decision to redact papers that had been provided, in unredacted form, to the criminal court hearing Howard's murder trial.
Ms Quinlivan said the police had to explain why it was apparently treating the coroner's court differently.
Mr Leckey echoed her concerns.
"I should be advised why the coroner's court is treated differently than other courts," he said.
"I have never understood it."
Mr Robinson suggested that officers who examined the papers for the inquest were different than those involved in the criminal trial and they may have adopted a "more prudent approach" to redactions.
He pledged to seek further information from the PSNI in regard to the issues raised at today's hearing and provide an update to the court at the next hearing on November 21.
The coroner's investigation into the disappearance of the teenager was postponed in May after a development in the police investigation prompted fresh digs for her body.
More than 92 new searches over the summer failed to find Arlene.