Banks have been accused of systematically feeding false and misleading information to NAMA in order to secure the maximum price for bad loans being purchased by the newly-established agency.
Fianna Fáil TD Michael McGrath called for the gardaí, the Financial Regulator and Office of the Director of Corporate Enforcement to investigate the matter.
NAMA Chief Executive Brendan McDonagh agreed that if they had relied on information from the banks without engaging in rigorous due diligence, they would have overpaid massively for the bad loans.
In its original draft business plan, NAMA anticipated it would acquire loans worth €77bn, with €62bn eventually being repaid by borrowers.
Banks told them that 40% of loans were performing. However, the reality was dramatically worse.
Only 25% of loans were performing, and some loans were not backed up by security at all.
Fianna Fáil's Mr McGrath accused the banks of deliberately misleading NAMA to extract the maximum price possible from the taxpayer for loans, some of which were in reality almost worthless.
NAMA's Brendan McDonagh added that many people had questions to answer.
He acknowledged that if NAMA had relied on the banks' information, they would have ended up overpaying massive amounts of taxpayers' money for loans.
The committee is to write to the Financial Regulator to pursue the matter.
'Banks behaving responsibly'
Senior officials from NAMA appeared before the Public Accounts Committee to report on the agency's first year.
The Chairman of NAMA said that he believes Irish banks are now behaving responsibly.
Frank Daly warned that the organisation will pursue all assets of developers to recover money owed to the taxpayer.
He said that where a debtor could not convince NAMA that it could meet repayment targets, it will face foreclosure.
The transfer of 11,000 impaired loans from the five participating banks to NAMA is almost complete.
The average discount is about 58% on loans, with a total value of around €73bn.
Now the focus will shift to pursuing the people who borrowed that money.
Mr Daly said that would include any assets that had been recently transferred to spouses or other parties, along with personal guarantees.
NAMA had instructed debtors to reduce their salaries to a quarter or a half of what it had been, he said.
On accountability, he said NAMA must report to the minister on a quarterly basis, as well as being audited by the Comptroller and Auditor General. He said it was subject to more scrutiny than any other body.
However, NAMA acknowledged that they had paid €60,000 per week for six employees from PricewaterhouseCoopers in the early days.
Mr McDonagh said it was a crisis time and they had to take experts from the UK on a temporary basis.
€6m profit
On 2 November a report from NAMA showed it recorded a profit of just over €6m during the second quarter of this year.
Finance Minister Brian Lenihan said NAMA was functioning well 'with transparency and sound governance'.
NAMA took in €117m in interest from borrowers in the three-month period, while it gave out €47m to developers to complete projects and run their businesses.
The State spending watchdog, the Comptroller & Auditor General, has also published an initial report on NAMA.
The report looks at the steps taken by NAMA so far to bring in structures and systems to run the agency.
The C&AG report said that while these were still evolving, the steps taken so far were 'reasonable'.
The report said NAMA had increased its staff numbers to 75, with the aim of bringing this to 100 by the end of the year.
