Oscar Pistorius Trial Day 12: Court readies to hear crucial questions that could decide the case

PRETORIA, South Africa – At one point, even Oscar Pistorius stifled a yawn.

It was a day spent in court squabbling over forensic camera angles, the presence of officers at the scene and the minutiae of police documentation, presumably aimed by the Paralympian's defense team to further discredit an already-tarnished police investigation.

But much of what the debate impacts is already "common cause" – meaning information agreed by both sides as to what happened on Valentine's morning last year, when Pistorius shot and killed his girlfriend Reeva Steenkamp.

It is what happens next that will be crucial.

Wednesday, as police ballistics expert Captain Chris Mangena continues the testimony he began on Tuesday, he will touch on several critical elements that could potentially make or break the prosecution's case of premeditated murder.

His ballistics report, handed up to the single judge Tuesday afternoon, is another critical puzzle piece in a murder investigation where the accused is also the only living witness.

To this point, the court has heard little of its contents, the rest to be revealed on Wednesday, when some crucial questions will be posed:

How far was Pistorius from the bathroom door which separated him from Steenkamp?

Professional measurements requested by Mangena put Pistorius' shoulder height at 61 inches while wearing prostheses, and 48 on his stumps. Mangena is expected to elaborate on the height at which the shots were fired, but both defense and prosecution agree that the double amputee was on his stumps when he fired through the bathroom door – a point that was previously expected to be an issue of contention.

Using steel rods, laser beams and Pistorius' account of the incident as a "benchmark," Mangena says he has tried to reconstruct the shooting at the scene.

During Tuesday's testimony, he said the laser used to represent bullet trajectory in his reconstruction of the event was positioned about seven feet from the toilet door. Add that to the 24 inches of Pistorius' arm length (measured to gun grip), and it comes to about nine feet where the athlete would have been standing from the door.

Pistorius says he felt vulnerable and afraid, believing there to be an intruder in the toilet, suggesting that he would have remained at some distance from the door, while firing through it. Conversely, the prosecution could argue that he feared any kind of debris or ricochet from the shots, demonstrating a rational thought process rather than outright panic.

How high were the bullets?

There are four bullet holes in the door, said Mangena, at heights of 36 inches, 41 inches, 39 inches and 38 inches above the floor. One bullet (the one which penetrated the door at 41 inches) ricocheted off the toilet wall in two places, eventually hitting Steenkamp's back, causing bruising there.

The ballistics expert says it appears the bullet travelled at a "downward trajectory" of four to five degrees. It is an assertion the defense is likely to embrace, suggesting the defense may attempt to show the athlete's shots at a low height were designed to maim rather than kill.

In what order were the bullets fired?

This is the most crucial question.

Experienced forensic pathologist Gert Saayman, who carried out Steenkamp's autopsy, said it would have been "unnatural" for her not to have screamed if the other wounds had preceded the devastating head injury which would have knocked her out and prevented any further cognitive function.

If the shots that hit Steenkamp in the right arm and right hip preceded the head wound, Pistorius would have heard her shouts of pain, alerting him to her presence behind the locked toilet door.

Various neighbors called as witnesses by the state prosecution have testified that they heard a woman screaming prior to and during "loud bangs." The defense says it would have been impossible to hear Steenkamp screaming from the locked cubicle from such a distance – but the witnesses remain adamant that they heard two distinct voices, a woman and a man.

If the first bullet caused Steenkamp's head injury, then she would not – as Pistorius' account states – have made a sound.

Whether or not Pistorius intended to kill Steenkamp – as the state alleges – will ultimately decide if he can be convicted of premeditated murder, a crime punishable in South African law by a life sentence in prison.

Much rides on the order of the bullets, and Mangena will need to use various factors to determine his conclusion, including, crucially, a fourth critical question.

What position was Reeva Steenkamp in when the shots were fired?

Mangena said four bullets were fired through the door. One hit the wall, he testified, meaning the other three hit the "target."

The ballistics expert says he requested Steenkamp's post-mortem photographs and clothing, to try to accurately reconstruct the incident.

If bullet trajectory shows the model was in a defensive position when she was shot, it suggests two crucial things: that she was aware that she was being attacked from the other side of the door; and critically, that the first bullet did not cause her incapacitating head injury, thereby allowing her to scream in pain.

If Steenkamp was trying to protect herself – as the bullet injury through the webbing of fingers suggests – it shows she was sufficiently capable of rational thought, able to shout and identify herself, as she faced the flurry of bullets.

Although Courtroom GD was not shown photographs of Mangena's investigation Tuesday, state advocate Andrea Johnson said it was because the photographic presentation accompanying his report included graphic photographs of Steenkamp's injuries. It is expected that the images, depicting bullet trajectory, will be shown publicly Wednesday.

It will be a critical day in court.

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