Pistorius' murder trial: Prosecutor challenges credibility of physician's testimony

The chief prosecutor in Paralympic runner Oscar Pistorius' murder trial has reportedly challenged the credibility of a physician who testified that the double amputee has an anxious nature linked to his disability.

Prosecutor Gerrie Nel said that the defence witness, physician Wayne Derman, could not be objective about Pistorius, who killed girlfriend Reeva Steenkamp on Valentine's Day last year in his home in what he has described as a mistaken shooting.

According to News.com.au, the prosecution says that Pistorius fatally shot Steenkamp through a closed toilet door after an argument.

The defence maintains that the double amputee runner has a deep sense of vulnerability because of his disability and a fear of crime, and it was a factor in the killing because he opened fire after thinking an intruder was in his house.

Under questioning, Derman acknowledged that his testimony did not amount to a 'forensic report' but disputed Nel's assertion that he could not give credible evidence because he was too familiar with Pistorius, having treated him over many years and travelled with him extensively, the report added.