The Jacob Zuma Foundation has labelled a judgment that found the former president in contempt of court “judicially emotional and angry”, as well as “not consistent with our Constitution”.

On Tuesday, the Constitutional Court found Zuma guilty of contempt of court and sentenced him to 15 months’ imprisonment.

The ruling came after Zuma defied the Constitutional Court’s orders to appear before the State Capture Inquiry and answer non-incriminating questions about his nine years in office.

The inquiry then brought a contempt of court application against the former president.

In a statement, the foundation said it was studying the judgment and taking legal advice on the options available to Zuma.

Edward Zuma, the son of convicted former president Jacob Zuma, says his father will not spend a single day in prison if he has anything to say about it.

“Our patron has never believed that he is above the law or the Constitution,” the foundation said.

“On the contrary, he has always insisted that he must be treated like every other citizen… Our patron has expressed doubts about the lawfulness of the Zondo Commission, the biased manner in which it is being conducted and the fact that it has been transformed into a ‘slaughterhouse’ and a forum in which all kinds of unsubstantiated and defamatory allegations have been made against him.”

The foundation ignored Zuma’s failure to defend his actions to the court when asked to submit an affidavit on what he believed his punishment should be if he were to be found guilty of contempt.

Instead, the former head of state sent a 21-page letter to the court, saying he would not be submitting an affidavit. He accused the court of exhibiting “political gimmicks”.

Zuma previously tried and failed to persuade Deputy Chief Justice Raymond Zondo to recuse himself.

He contended the State Capture Inquiry had carefully selected its witnesses from people disgruntled over his decisions to fire them or determined to badmouth the ANC and his leadership of the party.

“It is not a criminal offence to have a dispute with an administrative agency such as the Zondo Commission. Our patron has a legitimate disagreement with Zondo and has taken steps to have that dispute ventilated in the High Court,” the statement read.

The foundation said Zondo had ignored the High Court review process in the court, instead lodging an urgent contempt of court application in the Constitutional Court.

“The refusal of our patron to comply with an order which he considered unconstitutional cannot be characterised as wilful or ‘mala fide’,” the statement further read.

The foundation added that it believed the courts had acted with bias and denounced the judgment as a result.

Zuma had raised several concerns about Zondo’s partiality, citing a potential conflict of interest over an alleged previous friendship between the two men. The deputy chief justice denied all Zuma’s claims.