British writer of spy thrillers John le Carre said that the spy world was the "couch where the subconscious of each nation is confessed".

If this is true, the next few days could see some national psychoanalysis, as a procession of spy chiefs from the National Intelligence Agency (NIA), the army and the police appear before the Hefer commission.

But the chiefs have already indicated they intend to be anything but willing patients on Judge Joos Hefer's couch, since they see the process as potentially a major threat to their efficacy.

This contradicts sharply with the view of the commission. Leader of evidence Kessie Naidu said yesterday that the commission wanted from the intelligence agencies information that was relevant to its terms of reference for example, whether National Prosecutions Authority chief Bulelani Ngcuka was registered as a spy or an informer.

"We also want to find out whether there are any documents or information in the records of the intelligence agencies which may provide any evidence of Ngcuka or Justice Minister Penuell Maduna being agents or owing past favours to the apartheid regime," said Naidu.

Essentially, he said, the commission was not concerned with interfering with sensitive aspects of the intelligence agencies' work, but rather to secure limited information relevant to its terms of reference.

Ngcuka and Maduna have consented to any information that might be contained in the records of these agencies relating to them being made available to the commission. The NIA argued that it does not see the need for any of its representatives to appear at all, but the commission gave this idea short shrift and issued them with subpoenas.

So various representatives of the intelligence agencies will appear, but they intend to impress on the commission why it is impossible for them to supply the documents that Ngcuka's lead accuser, former transport minister Mac Maharaj, has asked for. It is also impossible for them to state categorically whether Ngcuka was a spy or not.

Their argument is that intelligence agencies run on the basis of their ability to secure information, and in most cases this means relying on informants.

It is extremely destabilising for the informants to know that the agencies could be forced to provide information about their identity, even if the circumstances are exceptional.

Society has very mixed views on providing information to state agencies, so the organisation's first duty is to protect the informants, without whom the agencies cannot really function.

Just knowing that the agencies could eventually provide information about the identity of their informants would have a terrible effect on recruitment.

What about the commission's offer that information could be heard in camera? This does not really make a difference, since the nature of the agencies' testimony will be incorporated into its finding. What about the argument that while this may all be true, the Ngcuka issue relates to something that happened more than a decade ago? The problem is that the agencies still have operatives on their books from 10 years ago. The rules apply as much to informants from the old dispensation as they do to informants from the new dispensation.

Does this not mean that the Hefer commission is a waste of time? No, they argue, because the agencies are convinced that Hefer can come to a decision without their participation.

But the crunch is: what will happen if the decision of the spy chiefs to decline to testify is not acceptable to the commission?

This route is shrouded in complications and speculation. One possibility is that there will have to be executive intervention and mediation, but there is no indication that the cabinet or President Thabo Mbeki is willing to mediate, should it come to this.

The only other possibility will be for the commission to formally charge the spy chiefs with contempt of commission. The result would be a court case. But, said an intelligence operative, "this would be really unfortunate".

The only real option is for the spy chiefs and the commission to come to an understanding that they will not be asked directly whether Ngcuka was a spy, but to co-operate in other ways. The question is whether they have been able to develop such an understanding in the short time that has been available to them.

Those scheduled to appear before the commission today are national police commissioner Jackie Selebi; divisional head of police crime intelligence Raymond Lala; his deputy Mlungisi Phego; director-general of the NIA Vusi Mavimbela; and former police commissioner Gen Johan van der Merwe.

With acknowledgements to Tim Cohen, Xolani Xundu and the Business Day.