Pretoria - Colonel JG Vermeulen returned to the stand in the High Court in Pretoria after a short adjournment, having just shown that Oscar Pistorius was not wearing his prosthesis when he tried to break down his toilet door.
Vermeulen told the court that the structure surrounding the door in court was an exact replica of the toilet cubicle in Pistorius's Silverwoods Estate home.
Defence advocate Barry Roux began his cross-examination by confirming some of Vermeulen's credentials.
Vermeulen is the commander of the material analysis sub-section at the forensic science laboratory.
He was testifying about a cricket bat Pistorius used to bash open the door of his toilet, and about the door itself, through which he shot his girlfriend Reeva Steenkamp.
Vermeulen told the court he had more than 29 years of experience in scientific analysis and completed almost 1400 forensic investigations.
Vermeulen admitted to the court that a microscopic examination of the toilet door had not been done.
Roux then asked about the State's argument that Pistorius was not on his prosthesis when he hit the door with the cricket bat.
At the bail application, the State had argued to the contrary, but Nel told the court that this was no longer the case.
Vermeulen also said Pistorius was the same height when both the shots were fired and when the door was broken, just not in the same position.
But Roux dug in his heels on his argument that Pistorius was standing, on his prosthetic legs, when the door was bashed.
Roux made Vermeulen demonstrate on his knees that if he lifted his feet, as though he had no legs, he would lose balance and could not have been able to break down the door.
Vermeulen admitted he had lost balance, but wasn't willing to testify on Pistorius's balance as an expert.
However, he did argue that someone who was born without legs would have greater balance.
He then said that if Pistorius could have maintained balance while shooting a firearm - as the defence has claimed - he probably could have been stable while using the cricket bat.
Roux then asked about what had happened to the rubber handle of the bat, and Vermeulen said he had received it in such a condition. He did suspect, however, that the rubber had been removed for fingerprint testing.
Roux indicated that the defence would try to prove that Pistorius could have made the same marks on the door while on his prosthetic legs.
The lawyer then asked about the possibility that additional marks on the door could have been created by investigators after the incident, but Vermeulen was unable to say he had seen images of the door on the day of the incident.
He then asked about the missing pieces of the door, which Vermeulen admitted he had not asked about, even though it could have “shed more light” on his findings.
Roux asked why such flaws in the investigation and the understanding Pistorius was not on his prosthesis were not compiled in a second report.
Vermeulen argued that these issues were presented by State prosecutor Gerrie Nel to the defence.
Roux then asked about what expected positions had been taken into account that could be used to create the marks.
Vermeulen said that usual positions, what would normally be expected while hitting, were taken into account.
The defence sent up one of its own to demonstrate an alternative position, where Pistorius could have been on his legs and standing further away from the door.
Vermeulen insisted that the marks on the bat would have been in different positions, and it would have created different indentations on the door.
When Vermeulen also demonstrated this alternative, he said: “I am in an unnatural position now, my lady.”
Vermeulen then said another mark on the bat also contradicted the alternative position, when concerning the second mark on the door.
Vermeulen then demonstrated that Pistorius would have had to bend his back, and push his pelvis outward unnaturally to create the second mark while wearing his legs.
Roux said that what was natural for Vermeulen was not necessarily natural for Pistorius.
“It matched (while standing) if I bent myself into an unnatural position,” Vermeulen said.
Roux then went on to query if the bat had managed to penetrate the door.
Vermeulen said it had, and when it was twisted out of the frame, a piece had broken off.
Vermeuelen’s testimony continues.