On May 8, the court heard an application by the Democratic Alliance to confirm a Supreme Court of Appeal ruling that the decision to employ Simelane was invalid.
In reading the judgment, Judge Zac Yacoob said: "The decisions taken and acts performed by Mr Menzi Simelane and actions by the [NDPP] are not invalid merely because of the invalidity of his appointment."
"The requirement that the NDPP must be a fit and proper person for appointment with due regard to his conscientiousness and integrity was not a matter to be determined according to the objective opinion of the president," he said.
The court was reviewing the appeal court's ruling in December last year that Simelane's appointment as NPA boss was "inconsistent with the Constitution and invalid" as Zuma did not apply his mind in the decision.
Simelane, who Zuma placed on paid leave after the decision, was appointed NPA boss in 2009 after the 2008 Ginwala inquiry severely criticised him.
The inquiry, which investigated the fitness of former NPA head Vusi Pikoli's ability to hold office, labelled Simelane's evidence before the inquiry as "contradictory and without basis in fact or in law" and blamed him for suppressing a disclosure of information. – Sapa