An inquiry into the fitness of National Prosecuting Authority (NPA) top advocates Nomgcobo Jiba and Lawrence Mrwebi to hold office commenced in Pretoria on Monday with acting NPA boss Silas Ramaite taking the stand.

The first day of the inquiry, which is chaired by retired Constitutional Court Justice Yvonne Mokgoro, focused on on prosecuting policies and the powers bestowed on the National Director of Public Prosecutions (NDPP) in overseeing cases.

Ramaite is one of the longest serving prosecutors at the National Prosecuting Authority. He has has acted as the NDPP three times. Jiba is the Deputy National Director of Public Prosecutions and Mrwebi the Special Director of Public Prosecutions.

Evidence leader, Nazreen Bawa, asked Ramaite what the functions of the deputy NDPP were.

"The functions are assigned by the NDPP, that will be the area of focus. For example, deputy NDPP responsible for prosecutorial services, that is general prosecutions," explained Ramaite.

Bawa directed Ramaite's attention to the powers of the NDPP. 

Ramaite said that if policy had not been followed during prosecutions then the NDPP had the power to review prosecution, after taking representations from involved parties.

He further explained that the powers of the NDPP must be in line with policy and the Constitution it operates under, and does not seek to unnecessarily interfere with prosecution.

President Cyril Ramaphosa established the inquiry last year.

Jiba and Mrwebi have been criticised for their handling of several high profile and controversial cases, including the decision to withdraw charges against former head of Crime Intelligence, Richard Mdluli.

Advocate Chris Jordaan is expected to testify after Ramaite.

The hearing continues.