Two alleged IRA informers in Donegal, Ms Adrienne Mc Glinchey and Ms Yvonne Devine, were "speaking to detectives" in Letterkenny where their information was considered credible, before they moved to Buncrana in August 1991, the Morris tribunal was told yesterday.
A retired detective sergeant, Mr Desmond Walsh, who was serving in Buncrana at the time the women moved there, said the impression he got from colleagues in Letterkenny was that the women, "especially Ms McGlinchey", were supplying "useful" information to the detective branch in relation to subversive activities.
However, Mr Walsh told the tribunal that the "largest ever" find of munitions - consisting of 2½ tonnes of rifles, machineguns, surface-to-air missiles and explosives - which was discovered in the early 1990s at White Strand, Co Donegal, was due to good police work and that the detectives had got no information from anybody.
While he knew little or nothing about either Ms McGlinchey or Ms Devine before they moved to Buncrana, he came to doubt their credibility as informers as he observed their activities.
Mr Walsh said: "Both ladies were running around town with bags with batteries, torches and balaclavas", and he could not rule out the possibility that they were being used by the IRA to complicate Garda intelligence.
Mr Walsh said that, while the women were seen to associate with known members of the PIRA, a contemporaneous note he had compiled which read "at the present time it is not believed that subjects are members of the PIRA" was accurate.
He referred to the discovery of a metal tripod in a bag which Ms McGlinchey had allegedly been seen carrying, and he said it was his belief that this was a home-made device and not something likely to be employed by paramilitaries.
He also referred to an occasion when gardaí uncovered an amount of fertiliser and sugar mix, which intelligence told them had been destined for Co Derry.
However, Mr Walsh said the mix was nothing like bombs designed by the IRA. Both women were observed walking in the vicinity of the find, he said.
Orders that rank and detective gardaí adopt a hands-off approach to investigating the women were causing problems among the gardaí based at Buncrana.
Questioned by the tribunal chairman, Mr Justice Morris, as to the source of these orders, Mr Walsh said he had had a number of conversations with Supt P.J. O'Connor who "made it clear that he did not want detectives to interfere with what she [Ms McGlinchey] was doing".
Mr Walsh said it was his understanding that Supt O'Connor considered Ms McGlinchey to be a good informer, and the superintendent did not want anyone other than Ms McGlinchey's handlers to have anything to do with her.
Mr Walsh told Mr Justice Morris that the Garda officer handling Ms McGlinchey was Det Garda Noel McMahon, who was instructed by Insp (now Supt) Kevin Lennon. Members felt that Det Garda McMahon had "a close relationship with Insp Kevin Lennon" which had led to preferential levels of overtime and caused disquiet among other members of the force. It was, he said, a situation which caused "disgruntlement"' among other detectives.
Earlier yesterday a retired detective sergeant, Mr Tom Sreenan, told the tribunal that intelligence information gathered from Ms McGlinchey was "pure rubbish".
Finishing his cross-examination after three days, Mr Sreenan said he had, over his years in the force, known many informers whose identity had never been released, "and they have all survived".
On the other hand, he said, the IRA had a method of conducting its own inquiries and the "code of practice" was to execute anyone the organisation thought was an informer.
The tribunal continues today.
