The former Minister for Education, Mary Hanafin, said the Junior Cert needs reform but teachers should not assess their own students.
Yesterday, the current Education Minister Jan O'Sullivan said she will be going ahead with changes to the Junior Cert, despite teachers unions not reaching an agreement on the proposals.
Mary Hanafin, who served as Education Minister from 2004 until 2008, thinks the marking of assessments should remain independent.
The Dun Laoghaire Rathdown County Councillor for Fianna Fáil, said the Junior Cert needs to remain standardised across all schools.
"It has to be assessed independently. I've got sympathies with the teachers on this," she said.
"I believe the parents themselves want to know that if you do an exam in Donegal or you do it in Dublin, if you do it in a vocational school or you do it in a fee-paying school, if you do it in rural Ireland or you do it in urban - it's the same exam and it has the same status."
"It's really important to protect that."