Cape Town - Johannes Christiaan de Jager fulfils the criteria of being a serial killer, a police forensic psychologist told the Western Cape High Court on Thursday.
“I do believe he fulfils those criteria. This classification is not a diagnosis,” police investigative psychology unit commander Brigadier Gerard Labuschagne told the court.
“It's based on the facts of the matter in which the accused is convicted on two separate incidents.”
De Jager, 49, was last month convicted of killing 18-year-old prostitute Hiltina Alexander in 2008 and 16-year-old Charmaine Mare last year.
Labuschagne was called by the State to give evidence in aggravation of sentence. He prepared a report for the court based on the docket, an interview with De Jager's girlfriend, the indictment, a post-fact visit to the crime scene, and his training and experience.
He had been involved in the investigation of over 110 serial murders and 200 serial rapes.
“A serial murderer is someone who murders at least two people at different times and for a primarily psychological intrinsic reason, not for material gain,” Labuschagne said.
Motives for the killings were typically anger, ideology, psychosis, and sexually-based.
Labuschagne said the modus operandi of such killers was most often to target black or coloured prostitutes.
There was normally one method of murdering and typically involved a sexual element, rape or partial nakedness, mutilation, or objects inserted into the anus or vagina.
It was his opinion that serial killers could generally not be rehabilitated.
“Those people who have multiple victims tend to be at a high risk of re-offending... and any sex offender is extremely difficult to rehabilitate since their crimes are linked to their sex drives.”
He said it was only when offenders admitted responsibility for their actions that rehabilitation was possible.
“[It is my opinion] that the accused poses and will continue to pose a real and significant threat to adult females.”
Labuschagne said he would recommend that De Jager receive appropriate psychotherapy from a clinical psychologist while in prison and that a copy of his report be considered should De Jager be up for parole.
Last month, acting Judge Chuma Cossie found the State had proved beyond reasonable doubt that De Jager raped Alexander vaginally and anally before strangling her.
His DNA was found on swabs taken from under Alexander's nails.
The State had also proved beyond reasonable doubt that De Jager killed Mare, dismembered her, and stole her cellphone.
During his trial, he insisted that he grabbed Mare in the bathroom last January because she was taking her time to get ready to go out, and she then slipped and fell.
He claimed she hit her upper body or head on the rim of the bath and never regained consciousness. He testified that he dismembered her and burned the torso because he was shocked and confused.
Cossie said the way De Jager burned the corpse indicated a deliberate attempt to conceal the evidence.