Correctional Services Minister Nosiviwe Mapisa-Nqakula says she has yet to receive a medical parole application from murder convict Clive Derby-Lewis.
Derby-Lewis, the co-accused in the 1993 murder of SA Communist Party leader Chris Hani, has twice been denied ordinary parole.
According to SABC News, his lawyers said the minister had withheld reasons for the latest refusal until the Public Protector had become involved in the case.
Derby-Lewis's legal representative Marius Coertze said he had been trying to get Derby-Lewis freed on parole for over three years. He said the Correctional Services department had been using double standards in the granting of parole.
"It seems that as the Public Protector got involved, we suddenly got the reasons which we were requesting a lot but could not receive."
Seventy-five-year-old Derby Lewis has served 18 years of his 25 years sentence.
His lawyer said he would only be eligible for parole again after two years, and that he was being treated for prostate and skin cancer.
The minister cited Derby-Lewis' lack of full disclosure and a lack of remorse for the crime as among the reasons he was being refused parole.
"You can't say that you express remorse on a matter when you have not disclosed fully to the South African public what led to the assassination," said Mapisa-Nqakula.
She said that by refusing Derby-Lewis parole she was setting an example that political assassination was a serious offence, SABC news reported.
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