A rare shaft of light is falling on interrogation methods used by South Africa's security police and the effects they have on persons detained under this country's tough internal security laws.
It comes from the inquest into the cause of death of Neil Aggett, a white doctor and trade union official found hanged in his cell last February while in security police custody.
In a warm, crowded courtroom in downtown Johannesburg, a parade of former security prisoners, many of whom knew Dr. Aggett, have gone before a judge describing their life while in the custody of security police. They describe varied conditions. But a composite picture from testimony so far suggests the police use techniques ranging from verbal intimidation to physical torture to gain information and confessions.
Under South African law, security detainees can be held indefinitely even though they may never be charged with a crime. While a board of review considers detentions longer than six months, the government has final say on whether a detention is continued.
Persons detained have no right to a lawyer or even to a visit from family, and they are beyond the reach of the courts. They are under the total control of the police who detain them.
Critics of the security laws have urged the government to adopt as a minimum a police code of conduct for dealing with detainees. But no such code has been adopted, and what goes on in security cells and interrogation rooms remains largely a mystery to South Africans.
Dr. Aggett was the 46th security detainee, but the first white one, to die in police custody. His death sparked a public outcry here and led to a large public demonstration by both blacks and whites.
Six months after Dr. Aggett's death, another security prisoner, Ernest Moabi Dipale, was found hanged in his cell.
The South African government has labeled Dr. Aggett's death a suicide, but the Aggett family is attempting to establish in the inquest that their son was induced to commit suicide - a crime in South Africa.
The counsel for the minister for law and order has promised testimony later by policemen that would refute the charges of the security prisoners.
Three former detainees told the court of sessions of interrogation in which they were repeatedly punched and slapped by police. All three had bags placed over their heads, and two of them alleged they were given electric shocks.
One of the detainees alleging electric shock, Shirish Nanabhai, complained of the assault to a district surgeon. The surgeon later wrote a report that ''scab-like wounds'' were found on Mr. Nanabhai's arms, where he claimed the shocks was administered.
Pramanathan Naidoo, a former detainee now serving a one-year jail sentence for harboring an escaped prisoner, told the court of ''exceptionally cruel treatment'' by the police during a seven-day interrogation session. He said he was periodically slapped and punched for giving ''wrong'' answers to questions about his membership in the banned African National Congress and the South African Communist Party.
He was made to stand naked, with his right wrist handcuffed to his right ankle. He was later beaten on the bottom of his feet. He claimed he eventually fell asleep on his feet from exhaustion and became aware he was talking to the police, without knowing what he was saying.
The counsel for the minister of law and order said Naidoo's affidavit was full of lies and half-truths and policemen would refute it.
The Aggett family appears to be trying to establish that their son's condition worsened noticeably in the few weeks prior to his death as a result of the way the police treated him. Several of the security prisoners who knew Aggett while in prison have testified on a sharp change they observed in Aggett's personality and physical condition.
Yvette Breytenbach, the last person outside the prison to visit Dr. Aggett, described him less than six weeks before his death as physically and mentally fit and ''optimistic.''
Security prisoners who saw him days before he died described him as unresponsive, and having difficulty walking.
Aside from the allegations of physical abuse, some former detainees offered glimpses of the severe mental stress of detention. Indeed, some critics of detention say the conditions are so stressful as to render confessions or information gained under them highly suspect.
Keith Coleman, a former detainee, admitted during testimony about Dr. Aggett's condition that although he could remember events of his detention, he had little recall of dates or the sequence of events.
Dr. Liz Floyd, Aggett's girlfriend, said she was verbally threatened and intimidated during her detention, but was not physically assaulted. She said one police interrogator spent nearly an hour intimidating her with stories of other detainees who had jumped to their death from windows.
Dr. Floyd reminded the court of the mental stress of detention. Referring to the 10th floor interrogation center of John Vorster Square prison in Johannesburg, she said: ''I think it is very difficult for people sitting in this courtroom to understand what it is like on the 10th floor, especially after three months of detention. Even though you know your rights, you begin to doubt them. Theoretically, I knew I was not guilty, but I began to doubt that.''
The inquest is continuing.