Businessman Cyril Ramaphosa and Johannesburg High Court acting Judge Kgomotso Moroka resigned on Saturday from civil rights body, Freedom Under Law (FUL).
The decision came as the organisation, headed by retired Judge Johann Kriegler, announced on Thursday that it would be challenging the Judicial Services Commission (JSC) decision not to probe Cape Judge President John Hlophe.
"We are deeply concerned that whilst we are members of the FUL's constituent governance structures we were not informed, let alone consulted about the organisation's decision to embark on this legal challenge," said Ramaphosa and Moroka in a joint statement.
Moroka is a member of the organisation's board of directors and Ramaphosa is a member of the international advisory board.
Meanwhile, Kriegler said the dispute between Hlophe and the Constitutional Court over whether he tried to influence pending court rulings in favour of Jacob Zuma last year before he became president could only be resolved through cross-examination.
He has made it clear that his aim was not to have Hlophe impeached, but to compel the JSC to do its duty.
Ramaphosa and Moroka said FUL's decision to challenge the Supreme Court ruling was a "major decision" that required the views of the members of the organisation's constituent bodies to be fully and thoroughly canvassed.
"This would be good governance. The failure to do so has put us in an embarrassing position and has compromised our ability to add value to the work of FUL."
They said the organisation's failure to consult had left them with no choice but to resign.
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