Former commissioners of the Election Commission must answer for their alleged wrongdoings and not be allowed to evade scrutiny due to their resignations, said Bersih.
The electoral watchdog was responding to attorney-general Tommy Thomas' argument that the tribunal is not academic.
"Bersih is of the view that former election commissioners who ran the 14th general election must be made answerable to the serious charges levelled against them.
"They should not be allowed to escape judicial scrutiny easily and conveniently for their conduct during the election with their resignations.
"This will send a wrong message to other public officials," said its steering committee in a statement this evening.
Previously, the tribunal's chairperson Shim Lip Keong raised a question whether the process would serve a purpose as the matter is now rendered academic since the six have stepped down.
The six former EC commissioners are Othman Mahmood, Mohd Yusop Mansor, Abdul Aziz Khalidin, Sulaiman Narawi, K Bala Singam and Leo Chong Cheong.
Meanwhile, Bersih said it would be unjust if the six were allowed "to roam free" and enjoy their pension, benefits and welfare while the allegations against them remained uncleared.
The electoral watchdog also urged the six to clear their names and exercise their right to defence if the former commissioners believe they have been falsely accused.
"If they are confident of having done nothing wrong, why would they resign once news of the establishment of the tribunal was reported in the press?
"Isn't this an attempt to thwart the proceedings of the tribunal?" it asked.
Bersih said the tribunal was set up to seek the truth by carrying out an investigation into the alleged past abuses and this would form the basis for possible action to be taken against the six.
Bersih, which pressed Putrajaya to form the tribunal last August, noted that the tribunal was also mandated to recommend appropriate action against the six to the Yang di-Pertuan Agong if elements of wrongdoing are established.
"It is worth noting that the appropriate action that the tribunal may make includes but not limited to the removal of the EC members from office.
"The tribunal may still put forward other recommendations in order to hold them accountable. They should not be allowed to escape justice through their resignations.
"If they are found guilty, their pension should be forfeited, at the very least.
"There is an urgent need to restore public confidence in the EC’s independence and impartiality, and the tribunal is the best way to do it," the watchdog added.
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