Pistorius has alleged that police tampered with the scene after he killed Steenkamp in his toilet, saying he thought he was shooting at an intruder.
He has already said that a fan, discs and curtains had been moved and watches were stolen from his bedroom, allegedly by police on the scene after the shooting on Valentine’s Day last year.
Pistorius testified that he picked up a pair of Steenkamp’s jeans which were on the floor to cover the blue LED light on his Pioneer amplifier which was bothering him, after he had woken up.
He heard a window slide open in his bathroom, said to Steenkamp “in a soft tone” to call the police and to “get down” as he approached the bathroom with his gun in the early hours of Valentine’s Day last year.
Later, when he had fired four shots he realised he had shot Steenkamp. She died in his home.
His counsel Barry Roux SC had earlier painstakingly taken the court through hundreds of photographs taken by Warrant Officer Barend van Staden, pointing out discrepancies and items the defence believed had been moved.
Pistorius was shown a picture of Steenkamp’s jeans taken after the shooting. He had insisted that the duvet had been on the bed and it had been moved to the floor.
Van Staden has testified that he found the duvet on the floor and after taking initial photographs, later opened it to photograph blood spatter he had observed.
As the court grew quieter, with people leaning forward to not miss a word, Nel asked Pistorius if the jeans, as seen in the photograph, were where he had left them, why were they on the duvet?
“There is one big problem. That denim is lying on the duvet,” said Nel.
“I don’t perceive that, My Lady,” said Pistorius, saying the angle of the photograph made it look like the jeans were on top of the duvet.
Nel said that in a close up it could be seen on the top portion of the duvet.
“I’m saying it doesn’t fit my version of what happened, My Lady.”
The only possibility was that the police moved it, suggested Nel.
“As they did with many other things, My Lady,” said Pistorius.
Pistorius is also charged with three contraventions of the Firearms Control Act, one of illegal possession of ammunition and two of discharging a firearm in public.
He allegedly fired a shot from a Glock pistol under a table at a Johannesburg restaurant in January 2013. On September 30, 2012 he allegedly shot through the open sunroof of a car with his 9mm pistol while driving with friends in Modderfontein.
He has pleaded not guilty to all charges.