By Louise Flanagan
Detective Inspector Fernando Luis dug through 21-year-old police case files to put behind bars the country's longest-active serial killer.
This week, the Kimberley High Court sentenced Tommy Williams to two life sentences plus 10 years for three murders - the first committed in 1987 when he was a minor and the last in 2008.
"This would prove to be South Africa's longest-lasting active series - 21 years from start to finish - however, fortunately, with only three bodies," said national police spokesman Senior Superintendent Lindela Mashigo.
In 2004, Williams killed a 13-year-old boy, Thabang Bihi.
Williams was a suspect at the time - he was friends with Thabang, the body was found in the grounds of a Warrenton house that Williams had stayed in, and he was later found with some of Thabang's possessions - but there wasn't enough evidence to prosecute him.
Then, in 2008, Norman Watermeyer, a 28-year-old disabled man, was killed in Roodepan, and Williams was again the suspect - he was last seen with Williams, his friend, and Williams later gave away some of Watermeyer's possessions.
Williams also made anonymous phone calls to Watermeyer's family claiming that Watermeyer was alive but had left town, fearing an upcoming operation. Williams even identified Watermeyer's body at the mortuary.
Luis had not been involved in 2004, but was the investigating officer for the Watermeyer murder.
"I thought, he got away in 2004 but he's not getting away now," he said.
"It eats you up inside."
In 2004 there had been rumours that Williams had found the body of a murdered child many years before, but nobody had been able to find that case. Luis was determined to find it.
He found that the murdered girl was Martha Botha, 8, and that she had been a neighbour of Williams.
It was Williams who "found" her body in 1987 near a sports stadium in Galeshewe. Serial killers are known to "find" bodies of their victims, so Luis wanted to look further.
He found Martha's mother.
"All she had was a death certificate," said Luis.
It gave the crucial date of death, so Luis went to the Diamond Fields Advertiser in Kimberley and searched newspaper archives until he found the 1987 front-page story of Martha's disappearance.
Armed only with the victim's name and date of death, Luis and a clerk searched a huge pile of dumped files at a police station.
It took a month to find the case file, which had the postmortem report and other key details.
They found the pathologist.
Luis said the investigation succeeded because they all worked as a team.
Mashigo praised their perseverance, saying old case files were often destroyed.
The commander of the SAPS investigative psychology unit of the Criminal Records and Forensic Science Services, Professor Gerard Labuschagne, called it a miracle that the old case file was found and praised Luis for "exceptional work".
Labuschagne gave evidence about the links and said that although the victims seemed different - a man, a teenage boy and a young girl - they were similar in that they were all vulnerable people and that Williams had connections to all of them.
He said there had been attempts to cover all the bodies, all three were probably strangled, Williams had links to all three, and he had "played some kind of role in the investigation" in each case.
Labuschagne said there was evidence linking Williams to the last two killings, but because of the time delay, the prosecution had to rely on circumstantial evidence regarding Martha's murder.