The United Democratic Movement (UDM) will get their day in court to argue for a secret ballot on a motion of no confidence debate in President Jacob Zuma.
The Constitutional Court will hear the matter on 15 May.
The UDM applied for direct access to the court last month after Speaker of the National Assembly Baleka Mbete said it was not within her powers to grant a request for a secret ballot.
The vote of no confidence in Zuma was due to take place on 19 April, when Members of Parliament were to be called back from their recess.
But opposition parties requested that the debate be postponed pending the outcome of the UDM’s court application.
The Chief Justice has now agreed to hear the case and says he will also hear oral arguments from four organisations, the Council for the Advancement of the South African Constitution, the Unemployed People's Movement, the Institute for Security Studies and the Shosholoza Progressive Party.
The Speaker and the Presidency are also permitted to respond to submissions made by these organisations before the appointed court date.