Judge Willem Heath has hit back against the claims made against him in both a letter from President Thabo Mbeki and in the president's address to the nation on Friday.

Reacting to the refusal of Heath to hand over confidential documents in his possession to Penuell Maduna, the justice minister and, via him, to the president, Mbeki expressed outrage.

"We cannot allow the situation to continue where an organ appointed by and accountable to the executive refuses to accept the authority of the executive," he said.

In his letter on Friday, Mbeki also accused Heath - whose investigating unit Mbeki excluded from the probe into the country's controversial R43-billion arms deal - of going to extraordinary lengths to "tout for work" with "a level of desperation" when he already had a significant backlog of cases.

Mbeki also cited a legal opinion on the arms deal to the effect that there was "no prima facie evidence in law that any person or persons committed a criminal offence". The opinion was based on a review of some the information apparently held by the Heath unit.

Heath said in terms of his governing legislation "there is no provision for accountability to the executive, but only to parliament and to the president as head of state".

Heath said the unit, in common with other agencies, relied on whistleblowers and had an agreement with them to protect their identity.

"This principle is respected all over. It was never alleged that the president or the minister would abuse the information. The public protector and other agencies are governed by similar provisions."

Heath quoted from the Special Investigating Units Act, which prohibits the disclosure of information regarding investigations except in so far as was necessary in the performance of his duties.

"The unit is not allowed to betray the trust of those persons or organisations who have supplied it with sensitive information. If the unit handed this information over then the whistleblowers and their identity could be uncovered."

Heath said that in terms of the agreement with his informants, the information would be handed back to them, though he would urge them to co-operate with the arms probe, continuing under the direction of the auditor-general.

He pointed out that all the necessary information needed for the president to make a decision was indeed handed over.

"The representations made to the minister of justice to be forwarded to the president for consideration were based on the auditor-general's report, the standing committee on public accounts hearing in Cape Town, the standing committee on public accounts report and its recommendations - and these representations were supported by the information in the possession of the unit. Although section 2 of our legislation requires only allegations to be submitted, the auditor-general's report, the hearing by the standing committee on public accounts and its subsequent report were based on facts that went beyond mere allegations," Heath said.

Heath also refuted claims that Mbeki had supplied him with the information he had requested at a meeting with the president in May 2000, as claimed in a statement issued by director-general Frank Chikane on January 4.

Chikane apparently later apologised for the error and explained that the requests for information had been referred to Alec Erwin, the trade and industry minister.

According to Chikane, Erwin had decided that it would require an extraordinary amount of time to provide the details that were required. As no probe was authorised at that stage, he refrained from answering the questions posed by Heath.

Regarding the allegation that he was touting for work, Heath said he had submitted an application for a proclamation, as he had done many times before.

"In addition to this the motivation was supported by the auditor-general's report, the Scopa [parliamentary standing committee on public accounts] hearing and the report and recommendations of Scopa. By submitting a motivation the unit was fulfilling its obligation to investigate any allegations of irregularities, corruption, fraud, negligence or maladministration."

Heath said he was very disappointed with the president's decision to exclude his unit from the arms probe, as he had received support from many people to continue with the investigation.

On the suggestion that there was no prima facie evidence regarding criminal offences, Heath said that prosecuting authorities investigated a case before they had prima facie evidence. "An investigation precedes even the level of prima facie proof.

"In any case, the unit investigates matters from a civil point of law and an arrest is not relevant to its investigation. The unit never claimed it had prima facie evidence of any criminal nature."

Heath said his unit's exclusion from the probe meant that the arms procurement process - with regard to possible civil action - as well as the analysis of the contracts and the tender procedures "will probably not receive the necessary focus that is required".

With acknowledgement to Sam Sole and Independent Online.