Gerrie Nel made the allegation during final arguments in the trial in a Pretoria courthouse, where the fathers of the Olympic runner and victim Reeva Steenkamp, a model and television personality, were in court for the first time since the trial began in early March. They sat at opposite ends of a long bench in the gallery.
Mr Nel said a criminal trial was a “blunt instrument for digging up the truth” but that he was confident of his case.
He said defence lawyers had argued that the double-amputee athlete acted in self-defence, fearing an intruder was in the house, but also raised the possibility that he was not criminally responsible, accidentally shooting Ms Steenkamp through a closed toilet door because he was “startled”.
“It’s two defences that you can never reconcile,” Mr Nel said.
The prosecution has argued that Pistorius intentionally shot Ms Steenkamp before dawn on February 14 last year after a quarrel. The defence has previously contended that he fired by mistake, thinking he was about to be attacked by an assailant in the toilet and that she was in the bedroom.
In addition to the murder charge, Pistorius faces three separate gun-related charges, one of which stems from his alleged firing of a shot in a crowded restaurant called Tashas in Johannesburg, months before he killed Ms Steenkamp. He has pleaded not guilty to all charges.
Some of the state’s written arguments and transcripts of past testimony appeared on screens in the courtroom. One section questioned Pistorius’ defence case:
Mr Nel said: “Is it putative self-defence? Is it an act of sane automatism? Did he have criminal capacity to act? Or was it all an accident as in Tashas Restaurant where he had the gun in his hand and it purportedly discharged itself?”
Because South Africa has no trial by jury, Judge Thokozile Masipa will decide with the help of two legal assistants whether Pistorius committed murder, is guilty of a negligent killing, or if he made a tragic error and should be acquitted.
The runner faces 25 years to life in prison if convicted of premeditated murder, and would also be sent to prison for years if guilty of murder without premeditation or culpable homicide.
Earlier, Judge Masipa told Mr Nel and chief defence lawyer Barry Roux that they had until the end of Friday to complete final arguments in court.
“Unless, of course, you want to work on a Saturday and perhaps Sunday, after church,” she said, smiling.