Ms Yingluck, who is also chairwoman of the National Rice Policy Committee, has been charged with dereliction of duty for failing to address allegations of corruption in the government’s rice-pledging scheme.
Lawyers preparing her defence have already been given a 49-page report detailing the NACC's probe into the rice subsidy scheme.
But they say the real report has more than 49 pages and have demanded to see the entirety of the anti-graft agency's evidence against Ms Yingluck, in order to properly defend charges against the premier.
Lawyers Norawit Lalaeng and Bancha Porameesanaporn went to NACC headquarters in Nonthaburi on Tuesday afternoon to formally request an additional copy of the entire report.
Mr Bancha said the legal team needed to be sure that they had received all documents related to the case and have sufficient time to study the documents. He said the NACC must not rush its ruling against Ms Yingluck, but allow their client the chance to fight the case.
If the NACC continues to insist that the full report contains only 49 pages, they should issue an official written statement to confirm that they will only consider evidence included in those documents when making their ruling in the case, Mr Bancha said.
The anti-graft agency is expected to issue its ruling on the case at the end of this month. It has already extended the deadline for Ms Yingluck to defend the dereliction of duty charges by 15 days.