Fianna Fáil Senator Mark Daly has said he has written to the Attorney General asking him to investigate NAMA for breaching the law in relation to the disposal of assets under its control.
Senator Daly told the Seanad that there was no transparency in the process that NAMA was pursuing.
He said people were being asked to get involved in what he called a scam, whereby the original borrower of the loan would buy back their own loan book for less than the current market value.
He said this practice was resulting in a huge loss to the taxpayer, running into the hundreds of millions.
He said the spirit of the law - as passed by the Oireachtas - had been broken.
He referred to Section 2:10, which states that the taxpayer must be protected.