Inland Fisheries Ireland (IFI) provided "inaccurate" evidence to a Public Accounts Committee (PAC) last week, members heard.
It comes after The Currency reported that IFI's senior management had knowledge into the investigation of a car crash involving a staff member in 2021. The vehicle was uninsured at the time.
Documents released to the website under a Freedom of Information (FOI) request also showed gardaí had been in touch with the agency on multiple occasions and requested access to staff emails.
Fine Gael TD James Geoghegan said they did not receive "full and frank answers to some very basic questions" when the IFI appeared before the PAC last Thursday.
He said these questions were over a "very serious allegation" that an agency of the State "knowingly provided false information" to gardaí.
Mr Geoghegan said it was "concerning" that these documents "were quite clearly in the possession of the IFI" last week and "known by persons who were in the room".
He said it was "very clear, we were not given full and frank answers". "Those documents should be given to us immediately," he said.
He said the IFI must come back before the PAC. Mr Geoghegan said he wanted to "put a line under issues" that have been ongoing for four or five years.
Chair of the PAC, Sinn Féin's John Brady said the "drip-feeding of information" was "deeply concerning".
"But what is even more concerning is the information that has come out," he said.
He said it "contradicts a lot of the testimony that was given to us here last week" and "calls into question timelines" and "who knew what, when".
"Some of the witnesses were actively involved in the compilation of the documents for the FOI request," he said.
"That information was fresh in the minds of a number of our witnesses," he added.
Mr Brady said "inaccurate" information was given to PAC and said it was "critical" that the documents be made available to the committee.
He said the IFI would be brought back before the committee in the New Year.
Fianna Fáil TD Paul McAuliffe said IFI's "next appearance is crucial".
"I just don't think it's acceptable," he said.
