A Newcastle serial murderer and rapist on Tuesday became the first person in South Africa to be convicted of crimes attributed to him only by a psychologist's linkage analysis.
He was convicted on Tuesday of two murders and two rapes after witnesses testified against him.
However, no "conventional" evidence was given against him for an additional two murders and an aggravated robbery.
The linkage analysis was accepted by Pietermaritzburg High Court judge Vivienne Niles-Duner who heard evidence against the accused to convict him of six crimes and at the same time convict him on the strength of the linkage analysis which described his criminal pattern of behaviour.
The psychologist, Dr Gerard Labuschagne, said that through linkage analysis, the serial criminal, Themba Sukude, had been creeping up on copulating couples, suddenly bludgeoning the heads of the men and then raping the women.
The crimes were committed in the Newcastle Trim Park from February 2003 to January 2005.
Niles-Duner said that Sukude, 31, should never be released from prison.
"Your murders were committed in a way which revolts in the extreme. You left the two women you raped traumatised and scarred for life, not only for the rapes but for the ghastly circumstances before the rapes.
"You have shown no respect for human life," she said.
Labuschagne, of the investigative psychology unit of the police's serious and violent crimes head office, said that linkage analysis was a powerful tool in the detection and prosecution of serial murderers and rapists.
The discipline could be used to identify which murders and rapes were committed by one person.
A serial murderer was one who had murdered at least two people at different times and often these murders had a sexual component. Typically such offenders did not stop until arrested, and they continued to commit crimes in spite of police investigations.
Their behaviour could vary with their experience, intelligence and motivation. As with many other human behaviours, the repetitive nature of their crimes gave them a sense of familiarity and control that allowed them to focus more intently on sexual and/or aggressive motives as the crimes continued. - Sapa