A ballistics expert has told the Oscar Pistorius murder trial that his analysis of the scene where the Olympic athlete shot Reeva Steenkamp differs from the reconstruction of the shooting by police investigators.
The study of the sequence and trajectory of bullets that struck Ms Steenkamp through a closed toilet door is at the centre of testimony over her body position at the time and how rapidly Pistorius fired the fatal shots with his 9 mm pistol.
It also relates to the defence's contention that police investigators made mistakes.
Police say Ms Steenkamp, a 29-year-old model and television personality, was cowering with her hands over her head when she was hit in the head by one of several bullets that struck her.
But today Wollie Wolmarans, a former police officer and now a private ballistics expert, testified for the defence that he did not believe her left hand was over her head.
The painstaking debate over detail reflects the defence's efforts to show that Ms Steenkamp was not arguing with Pistorius after fleeing from him when she was shot in the pre-dawn hours of February 14, 2013 - as the prosecution contends.
Mr Wolmarans, who was testifying for the second day at Pistorius' trial, also said it was his opinion that the four shots were fired in "fast succession," apparently supporting Pistorius' contention that he shot rapidly and in panic after thinking there was an intruder in the cubicle.
The prosecution believes there could have been a gap between the first and the following three shots, arguing Pistorius fired with deliberate intent to kill.
Pistorius, 27, is charged with premeditated murder for Ms Steenkamp's shooting death.
He says the killing was accidental because he mistook her for a dangerous intruder about to come out of the cubicle and attack him. The double-amputee athlete held his hands over his ears at times in court when Mr Wolmarans talked about Ms Steenkamp's wounds.
Prosecutor Gerrie Nel argued Mr Wolmarans' opinion about Ms Steenkamp's position when she suffered some of the gunshot wounds didn't make sense. Mr Nel cited the small size of the toilet cubicle and blood and tissue spatter on a wall and the toilet lid.
Before beginning his cross-examination, Mr Nel invited the judge and her two assessors to leave their seats and take a closer look at a reconstruction of the toilet cubicle that has stood in the courtroom for much of the trial, and where the prosecution had prepared a display today.
The judge was led by the hand through the courtroom by a police officer before the police's ballistics expert sprayed a substance into the reconstructed cubicle. Red laser beams became visible in the exhibit to show possible bullet trajectories.
Judge Thokozile Masipa, dressed in her traditional red robe, pointed with her finger into the cubicle at one point and appeared to ask Mr Nel a question.
Judge Masipa will deliver a verdict because South Africa does not have trial by jury. Pistorius faces 25 years to life in prison if convicted on the premeditated murder charge.