A forensic voice analyst has been accused of carrying out a "flawed'' examination of secretly recorded conversations with three alleged members of the dissident IRA.
Professor Peter French was also accused of not carrying out an independent examination of the tapes without assistance from PSNI detectives.
The covert MI5 bugging operation allegedly captured 52-year-old Colin Duffy, Alex McCrory (58) and 51-year-old Henry Joseph Fitzsimons discussing a failed attempt to murder police officers in north Belfast in 2013.
During a third day of cross-examination at the non-jury Diplock style trial before Mr Justice O'Hara, defence counsel Barry McDonald QC for McCrory put it to prosecution voice analyst expert Professor French that he had not carried out an independent examination of the tapes as he had first suggested.
Mr McDonald said it was clear from the records of a preliminary enquiry held in 2016 that Professor French already knew the names of the suspects - who were given the ciphers of 'M1, M2, M3' - and had carried his work alongside a police transcript of recorded conversations from a car stop, telephone calls to an insurance company and a heavily bugged laneway in Lurgan.
Said the defence QC: "Why did you need the details of the three individuals?"
Professor French replied: "Well, I didn't."
Mr McDonald put it to the expert witness: "You were getting more help from the police..."
Professor French: "Well it didn't look like we requested that help. It is possible. I don't think so. I can't think why I asked for it. It would not have helped me."
Mr McDonald put it to the witness that "you were getting a steer about who was M1, M2, and M3. How did you get that particular steer?"
The witness replied: "The names were written in the margins of the (police) transcript."
The defence lawyer said in order for the witness to identify who M1, M2 and M3 were, the witness would have had to go through the transcripts to see how the police had attributed names on the voice recordings.
"You had to go looking for the transcript in order to see who they were, isn't that right?" asked Mr McDonald.
Professor French replied: "Yes, in order to compare voices."
Mr McDonald told the witness: "This was a deeply flawed process and you would not do it again today in this way."
But Professor French said during the examination of the voice recordings "the content of the police transcripts were not swollen wholesale".
He also stated that during his analysis of recordings he had found over 30 attributions from the police to 'M1, M2 and M3' which were incorrect.
Duffy, Fitzsimons and McCrory, whose addresses cannot be reported, deny preparing and directing terrorism, and membership or professing to be members of the IRA.
Fitzsimons and McCrory are also charged with and deny attempting to murder police in the convoy, and possession of the two AK47 assault rifles and ammunition used in the 2013 attack.
The trio were allegedly covertly recorded and videoed under an MI5 operation code-named 'Operation Idealistic" on December 6, 2013. At hearing.