"We are taking this matter to court because we feel it is a constitutional matter and the minister has no power to suspend the head of the Hawks," Francis Antonie, director of the Helen Suzman Foundation, told The Anadolu Agency on Monday.
He said the foundation had approached the High Court in Pretoria to reverse the suspension of Lt. Gen. Anwa Dramat, the national head of South Africa's Directorate of Priority Crime Investigation, commonly known as "the Hawks."
The case will be heard in court on Thursday.
Police Minister Nkosinathi Nhleko suspended Dramat last month following a probe into the latter's alleged involvement in the rendition of four Zimbabwean suspects five years ago.
According to reports, some of the Zimbabwean suspects were tortured in Zimbabwe while others simply went missing.
"His suspension came three weeks after the Constitutional Court ruled that the minister cannot interfere with the hiring or firing of the Hawks' boss," said Hellen Zille, leader of the Democratic Alliance, South Africa's main opposition party.
She said the hiring and firing of the Hawks chief could only be done with the approval of two thirds of the National Assembly.
Zille noted that Dramat's suspension had come shortly after he had requested that a number of high-profile cases – including a probe into the controversial upgrade of President Jacob Zuma's rural home – be handed over by police to the Hawks for investigation.
In 2014, South African Public Protector Thuli Madonsela accused Zuma of using massive public funds to renovate his country estate.
The renovation was supposed to have cost the state some $2.5 million, but with lavish upgrades, total costs skyrocketed to a whopping $23 million.
"The Democratic Alliance wants parliament to review Minister Nhleko's decision to suspend Dramat in contravention of a Constitutional Court ruling," said Zille.
"We believe there is a case for parliament to find that the minister is not fit to hold office," the opposition leader added.