Questions remain about the secret ailment that afforded former South African president Jacob Zuma a free "get out of jail card" on account of his health. 

Former president Jacob Zuma was still receiving medical treatment on August 6, before he was expected to return to his home at Nkandla in KwaZuluNatal after his release from a South African prison the previous day. 

Zuma, who was serving a 15-month prison sentence, was granted medical parole over the weekend. South Africa's highest court, the Constitutional Court, sentenced Zuma for contempt of court after he refused to testify before the state capture commission of inquiry chaired by Deputy Chief Justice Raymond Zondo. The commission was established to probe corruption during Zuma’s almost decade-long presidency. 

But Zuma only served two months of his 15-month-jail term in prison.

In a statement released on Sunday afternoon, South Africa’s Department of Correctional Services said that it had received a medical report that recommended Zuma was eligible for medical parole.

The exact nature of Zuma’s illness was not disclosed, but the department highlighted that “apart from being terminally ill and physically incapacitated, inmates suffering from an illness that severely limits their daily activity or self-care can also be considered for medical parole."

Zuma's medical parole means that he will complete the remainder of the sentence in the system of community corrections.

"He must comply with [a] specific set of conditions and will be subjected to supervision until his sentence expires."

Zuma’s exact ailment remains a mystery. He was taken to hospital for “medical observation” in August, and his lawyers have said that his ailment has got continuously worse since his incarceration. 

The former president is also on trial for corruption, but his scheduled appearances in the Pietermaritzburg High Court had to be postponed on several occasions because of medical treatment. The letter from his doctor, presented by his lawyers to court, did not provide any details and all his medical documents remain confidential.

The man who signed off on Zuma’s medical parole is the national prisons commissioner, Arthur Fraser. Fraser was a staunch ally of Zuma while he was president, and has already come under fire for his decision. 

The leader of official opposition, the Democratic Alliance’s (DA) John Steenhuisen, said it should also "be noted that the medical parole was granted by Zuma's former spy boss, Fraser – a man deeply implicated in the corruption of the State Security Agency and accused of running an illegal parallel intelligence structure".

Steenhuisen said the decision was entirely unlawful and made a "mockery" of the Correctional Matters Amendment Act.

Correctional services spokesperson Singabakho Nxumalo, however, defended Fraser’s decision, saying he was entirely empowered to prescribe conditions of medical parole after studying the necessary medical documents. 

The prisons department also explained that even if Zuma’s condition improved, he would not necessarily be sent back to prison. His parole conditions are also confidential, Nxumalo emphasised. 

Nxumalo added that medical parole can only be revoked if an offender does not comply with the placement conditions. He asked South Africa to afford Zuma the necessary dignity as he continues to receive medical treatment.