Judge Robert Nugent, who is heading the Commission of Inquiry into tax administration and governance at the South African Revenue Service, on Wednesday urged any parties who wished to counter evidence submitted before the hearing to come forward with their version.
Nugent's plea comes after several SARS officials made startling claims about a dire operational system that, by their accounts, almost incapacitated the tax collection service.
Evidence of a culture of fear, internal investigations of staff, and incapacitation of experienced employees has dominated the hearing since it resumed on Tuesday.
"Anyone who has any information to counter any information that has been given is free to come forward," said Nugent.
News24 earlier reported that SARS former chief of business and individual taxes, Jonas Makwakwa, had written to Nugent to ask him to subpoena the tax agency to issue information which he says he needs for his testimony at the hearing.
The commission, which is investigating allegations of financial misconduct at the tax service, has heard a range of evidence from SARS employees, including former heads of the now-disbanded investigating units which handled high-profile tax cases.
Evidence leader Carol Steinberg said so far only two people had come forward with an intention of responding to some of the evidence since the commission began its work in June.
She did not reveal the identities of the individuals.
Witnesses have described how the new operating model adopted by the tax service in 2015 had impaired the service and led to the disbanding of key investigating units.
The disbanding of the units is said to have negatively impacted tax collection.
One of the key witnesses, Pieter Engelbrecht, the former head of the unit charged with investigating high-risk cases, including high-net worth individuals and those linked to the illicit tobacco, trade painted a dire picture of delays in decision-making processes, after the unit was disbanded, with a lack of clear direction and leadership.
The witnesses were directed not to refer to any people implicated in their evidence by name.
The inquiry will hear evidence until the end of the week and resume again next week for four days.
* Sign up to Fin24's top news in your inbox: SUBSCRIBE TO FIN24 NEWSLETTER