A forensic expert called by Oscar Pistorius’s defence team has contradicted some of the State’s forensic evidence and described police as being unprofessional and careless around crime scenes.
Roger Dixon said he had worked for the police’s forensic science laboratory for 18 years, and had seen police officers compromising crime scenes and contaminating evidence by failing to take precautions.
“In my experience of crime scenes, it’s unfortunate, people walk all over the place,” he told the High Court in Pretoria on Tuesday.
“Evidence is compromised – it’s not in a pristine state in which you’d like to examine it.”
Dixon was referring to the door to Pistorius’s en suite toilet cubicle, photographs of which showed it with shoe prints.
Pictures taken earlier had shown no such marks on the door.
“(The shoe print) can only happen when somebody walked on it. It is highly unprofessional… unless there’s a pressing need to save a life,” said Dixon.
It is not clear how the shoe print came to be on the door. When cross-examined about it last month, Colonel Johannes Vermeulen, commander of the material analysis section at the forensic science laboratory, said: “I don’t know.”
Another crucial piece of evidence Dixon picked up was fibre from Pistorius’s sock embedded in the door. The defence argues it got there when Pistorius tried to kick the door open.
Dixon also examined the right sole of Pistorius’s prosthetic leg, and found it to have been damaged as it hit the door.
“That can only come from a hard kick,” he said.
Vermeulen had not tested this mark, because he had been asked to test only the marks made by the cricket bat on the door as Pistorius bashed it open.
This led Barry Roux SC, for the defence, to say police investigations were designed to favour the State’s case, compromising Pistorius.
Vermeulen believed the sock fibre became embedded in the door when Pistorius stumbled on one of the wooden door panels lying on the bathroom floor as he carried Steenkamp downstairs.
Dixon disagreed. “That can only be from a hard kick,” he said, pointing to a picture beamed on screens in court and showing door varnish left on the athlete’s prosthesis.
He agreed with Vermeulen on the sequence in which the bat and bullets hit the door. The bullets were fired first, then the door was hit three times with a cricket bat, he said.