Former international relations and cooperation minister Maite Nkoane-Mashabane acted unconstitutionally when she granted former Zimbabwean first lady, Grace Mugabe, diplomatic immunity.
This is the argument of the counsel representing the Democratic Alliance in an application by lobby group AfriForum against the decision by Nkoane-Mashabane to grant diplomatic immunity to Mugabe.
The case relates to an incident that happened in 2017, when the 52-year-old wife of former president Robert Mugabe allegedly beat up model Gabriella Engels at a Johannesburg hotel where her two sons were staying.
The matter is sitting before acting Judge Bashier Vally in the North Gauteng High Court in Pretoria.
The DA's legal heavyweight, advocate Anton Katz SC said: "Point two is that what the minister of international relations did in relation with Grace Mugabe was inconsistent with the Constitution.
"The day that Robert Mugabe ceased to be the president of the country, it would seem that there is an argument to be made that Grace Mugabe's immunity ceased to exist."
Katz asked whether any immunity granted while Mugabe was still the president, was still valid.
"There was an event, of an alleged assault GBH, she got spousal immunity for that event."
Katz said the minister must explain the status of the immunity to the court.
"She has gotten it on the virtue of her office, not because of her work. That immunity ceases once you are no longer in office," he added.
'The minister accepts that the immunity no longer exists'
Council for the Department of International Relations and Cooperation, Hilton Epstein SC, then interrupted.
"The minister's case is that she was allowed to grant spousal immunity under international customary law... Whether Mr Mugabe is no longer the president, the minister's position is that the law must take its course."
Epstein said: "The minister accepts that the immunity no longer exists."
Katz interrupted, saying: "He has just told the court that his client acted unlawfully."
Vally said he did not think that Katz understood what Epstein was saying.
Katz suggested that South Africa's domestic laws only granted immunity to heads of state, and not to their spouses.
"The minister says there is a woman who commits assault on another woman, the perpetrator is the spouse of a head of state, her country writes to the minister, saying please grant her immunity.
"Then the minister says, because of international law, she already has immunity."
Katz submitted that the minister didn't seem to understand the law herself.
"...One would at least expect the minister to understand the power properly, before acting."
Katz said the court should consider the matter, in the interest of justice.
The case continues.