A former Co Donegal garda superintendent said he had been isolated and kept in the dark about suspicions that Bernard Conlon was making false statements.
Kevin Lennon said that when he received a report in July 1998 that Mr Conlon said he had been threatened by two men with a silver bullet, he had believed it.
Mr Conlon has alleged he was told to be caught in the McBreartys' nightclub in Raphoe late-night drinking and be a State witness against them. He said he was told by Det Sgt John White to set up the McBreartys.
He also alleged Sgt White told him to make up a story that two men called to his house in Sligo and threatened him with a silver bullet not to go ahead with the court case. Sgt White has denied all allegations against him.
Yesterday, Mr Lennon said nobody told him at any stage that there were any doubts about Mr Conlon. When the report was sent up to him, he believed it.
Later, when the Carty Garda internal investigation team arrested Mr Conlon, he said he knew nothing about it.
"They told me nothing, they isolated me and kept me in the dark. I was entitled to be told there were suspicions that he was planted as an agent provocateur," he said.
He wanted to find out about the statement Mr Conlon made about being "found on" the premises.
He contacted Sligo where Mr Conlon made the statement and talked to Garda John Nicholson.
"The perception now is that Garda Nicholson knew a lot more than he was saying. He never once told me there were doubts about Mr Conlon," he said.
Garda Nicholson, now retired, was prosecuted for submitting forged certificates of employment for Mr Conlon for court appearances. Mr Lennon said Garda Nicholson never once told him the certificates were forgeries.
"Events happened in Sligo and I didn't know anything about it. I was hoodwinked and misled by Sligo. I was told nothing," he said.