The chair of the Economy Committee says it's essential the Public Accounts Committee (PAC) is allowed to fully investigate the renewable heat incentive.
The botched scheme could cost tax payers four hundred million pounds.
Newry and Armagh MLA Conor Murphy's calling on political and commercial interests to be put aside so that the Committee can fulfil its remit without being stone-walled.
Speaking yesterday he said, "It is essential that the PAC is afforded every opportunity to establish all the details concerning the operation of RHI and particularly the specific reasons behind the spike in applications to this scheme which can only compound the financial challenges created by Tory cuts to our public finances.
"Despite three open public evidence sessions with the two permanent secretaries in charge of DETI from the beginning in 2012, until the close of the RHI in 2016, there is still no transparent, comprehensive or satisfactory explanation as to what has gone so badly wrong.
"No political or commercial interests should be allowed to impede the PAC fulfilling its remit. It must have access to all the available evidence. That means there should be full disclosure of all beneficiaries from this scheme."
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