Pretoria's pressure on press puts credibility of S. African journalists on the line

The press in South Africa is being buffeted by what some feel is a particularly severe and dangerous attack by the government. The government, in its efforts to root out opponents linked to recent black unrest, is calling on local journalists to aid its investigations - a role many reporters find potentially compromising.

Taking a long view, many South African journalists fear the government ultimately is going to threaten the ability of newspapers to carry vital black views to their largely white leadership.

Subpoenas against reporters to provide evidence for police investigations ''have been falling like confetti'' in recent weeks, says John Allen, an official of the Southern African Society of Journalists. By his count 12 journalists have been called on by the South African police to provide information.

Mr. Allen says he has never seen such a ''sustained assault'' on the press, which to begin with operates under a wide range of laws that restrict what can be published in South Africa.

The press is not free in South Africa, but neither is it as restricted as in many other countries.

''One wonders if there isn't a formal (government) decision to use the press more to get evidence against people,'' says Allen, referring to the recent subpoenas.

The government's long standing suspicion of the press has produced not only prohibitive laws but periodic threats.

Earlier this month South African President Pieter Botha threatened to reconsider the findings of a commission that in 1982 recommended stricter control of the press.

The commission's report was rejected. But when some newspapers recently raised questions about gratuity payments to Mr. Botha, he wondered out loud if it were not time to reexamine the report or the press.

One case causing particular concern is the government's subpoenaing of Gary van Staden, a political reporter for the Johannesburg Star newspaper.

Mr. van Staden is being asked to reveal the identity of a group of people who asked him to a press conference where they made a statement but insisted they not be identified.

They said they feared for their own safety and also feared being detained by the police.

Revealing sources after guaranteeing them anonymity raises severe ethical problems for journalists. But while there might be a case for doing so in some circumstances, Harvey Tyson, editor of the Star, says South Africa's system of detention without trial ''wipes out arguments based on the cause of justice.''

The 11 other cases involving reporters and the editors of three Cape Town newspapers concern providing evidence to the police.

Allen says generally there is less objection to reporters or editors being called on to give evidence which may help solve a crime.

But in South Africa's highly charged political atmosphere there are important nuances to consider.

For instance, several of the reporters recently subpoenaed are to be questioned in connection with interviews with Thami Mali.

Mr. Mali has been detained without charge apparently in connection with his involvement in a two day black workers' strike in early November.

Since he has not been charged, Mali is regarded by many as a political prisoner. And some feel it is improper to provide evidence against him.

Also, some see an ethical dilemma if the police ask reporters for information Mali may have provided ''off the record.''

Allen says the great danger is that blacks will begin to see a danger in talking to the press. This could shut off one of the few remaining channels of candid communication between whites and blacks.