Tag Archives: Ballistics

Dueling Experts and the Oscar Pistorius Case

On Valentine’s Day, 2013, noted South African Olympian Oscar Pistorius, who gained fame for competing in the 2012 London Olympics despite not having legs below his knees, fired four gunshots through his bathroom door to kill his live-in girlfriend, model Reeva Steenkamp.  Now, from halfway across the globe, the ensuing murder investigation has captured the attention of the American public and kept legal experts and laymen wrapped up in the twists and turns of the trial.

As the case unfolds, expert witnesses have emerged as important characters in the drama by providing factual analysis to support or contradict Pistorius’ claim that he fired the shots in self-defense under the belief that the person behind his bathroom door was an intruder.  A recent two-week adjournment provides opportunity to pause for analysis of the impact the critical expert witnesses have had.

Experts for the South African Prosecution

Lead South African prosecutor Gerrie Nel notably called experts in ballistics and pathology to help contradict Pistorius’ claim that he fired on what he suspected was a home invader.  Police ballistics expert Chris Mangena and pathology expert Gert Saayman were both called by Nel in order to call into question Pistorius’ testimony about the evening and the fatal encounter.

Ballistics expert witness Mangena: Of critical issue to Pistorius’ claim that he was unaware that the person behind his bathroom door was Steenkamp is the order in which the bullets hit her. Both sides agree that the fatal wound was administered by a shot to the head that would have caused instant death, and the prosecutor’s ballistic expert witness testified that the head-shot was the third and final bullet to make contact. Mr. Mangena further testified that Steenkamp was struck with two other bullets – one in the hip and one in the arm – both of which would have caused pain and given cause for the victim to scream prior to being killed with the third shot. Mr. Mangena also claimed that the pattern of wounds on the body would make Pistorius’ story that he fired two rapid “double taps” impossible, meaning that he would have had the opportunity to hear her scream and identify her before firing the fatal shot.

Pathology expert witness Saayman: Gert Saayman’s testimony of the gruesome wounds suffered by Ms. Steenkamp was highlighted by the defendant vomiting in court at the graphic description. However, his most contested claim was in regards to something far less serious: the contents of the victim’s stomach. Pistorius has told the court that he and Steenkamp were in the bedroom by 10 PM, and asleep shortly after, and that he thought she was still sleeping next to him when he discharged the firearm against the suspected intruder. However, according to Saayman, Ms. Steenkamp had probably eaten around 1 a.m. – meaning that the two were not together in bed from 10 p.m. until the time of the shooting.

The prosecution’s use of expert witnesses was well crafted, and targeted key points of Pistorius’ story of how the shooting took place. Defense attorney Barry Roux aggressively questioned both, and shaped his own expert witness list to directly challenge their findings.

Pistorius Calls Pathology Expert Jan Botha

First to testify for Pistorius was pathology expert witness, Dr. Jan Botha. Dr. Botha opened by calling into question the methodology used by Dr. Saayman when he determined that Steenkamp had eaten only two hours prior to the shooting, calling the claim to be questionably supported by facts. Dr. Botha then turned his attention to the claim that Pistorius would have had the opportunity to hear the victim scream before firing the fatal shot. Although he did not speak to the order in which Ms. Steenkamp’s wounds were caused, Dr. Botha did testify that the pain caused by the impact of the bullets would have caused her body to go into shock – making it highly unlikely that she would have cried out unless there was significant time between the shots.

Pistorius Recent Defense Expert Creates Confusion

The most compelling expert presented in the case has been Pistorius’ forensic expert witness, and apparent jack-of-all-trades, Roger Dixon, whose contradictory account of the shooting led prosecutor Nel to question his qualifications and create doubt about the defendant’s version of the incident.

Dixon, hired by Pistorius as an expert witness to support his version of the shooting, is a former police forensics investigator who now teaches geology. During a dramatic three-day affair, Dixon initially testified to confirm Pistorius’ account that the room was too dark for him to recognize that Ms. Steenkamp was no longer in bed with him. He then contradicted ballistic expert Chris Mangena’s testimony that the victim was in a defensive position – indicative of an argument between her and Pistorius – when the shooting started by testifying that she was leaning towards the door handle in preparation to come out of the bathroom – supporting Pistorius’ account that he reacted to an unfamiliar noise. Finally, Dixon conducted visual and audio tests to dispute testimony from Pistorius’ neighbors that called into question the timing of the gunshots and the position the shooter was in.

Sparks began to fly when Mr. Dixon was cross-examined by prosecutor Nel for having a confessed “laymen’s understanding” of ballistics, for not taking Pistorius’ height into account when recreating the scene, and for contradicting the defendant’s own testimony of what the scene looked like during and after the shooting. Because Dixon is a geologist, and not actively conducting forensic investigations, he was taken to task for being unqualified and for providing testimony that could prove unreliable – calling his entire expert witness credentials into question.

Judge Thokozile Masipa, who is solely responsible for determining Pistorius’ guilt in South Africa’s non-jury system, has delayed the trial for two weeks following the up and down testimony of Mr. Dixon. The defense will resume on May 5th, and will likely attempt to reconcile Mr. Dixon’s testimony with Pistorius’ version of the events with another independent forensic expert witness.