Oscar Pistorius case: The key questions

South African Olympic sprinter Oscar Pistorius appears in court in Pretoria on 22 February 2013 Image copyright AFP

Don't expect another tearful, edge-of-seat, courtroom drama just yet.

South African Paralympic star Oscar Pistorius returns to the dock in Pretoria on Tuesday, but it will be a brief affair - perhaps just a few minutes - as the prosecution asks the magistrate for more time to complete its investigations.

And it won't be the last postponement granted in a murder case that is unlikely to come to a full trial until early next year.

But the world has barely glimpsed in person Mr Pistorius, who is accused of murdering his girlfriend Reeva Steenkamp on 14 February, since his bail hearing, and so, inevitably, his fleeting appearance in court this week will offer us all a chance to scrutinise the man himself, and to analyse the state of this slow-moving legal drama.

"Mentally, he's still battling," Mr Pistorius's coach, Ampie Louw, told me.

"Physically, he's in good shape. Mentally he's up and down. This is going to be a long road."

Mr Pistorius has largely stayed out of sight at his uncle's house on the edge of the capital, Pretoria, making only a handful of confirmed excursions.

"It's not good for him to just do nothing. We've got him in a routine of home training," said Mr Louw.

"We've equipped a gym in the house to keep him occupied and busy. We can't lose nine years [of training]. We have to try to maintain things.

"The last two months, he has picked up slowly, but now he's looking fine.

"We will leave it to Oscar to guide us as to when he will be mentally ready to go to a [running] track."

As for the murder case itself, for now the ball remains firmly in the prosecution's court as they continue to prepare their docket, with forensic evidence likely to play a central role.

You may have seen these photos purportedly of the crime scene that were presumably leaked by someone in the police. Various people have tried to suggest that the position of the bullet holes in the door helps one side or other's case. My sense is that they mean nothing on their own.

Once the prosecution have concluded, they will reveal their evidence to the defence team, which will then almost certainly request more time for its experts to examine and challenge the prosecution's conclusions.

Key questions

At the centre of the forensic investigation is a door, and attached to it are two fundamental questions.

Firstly, how close was Mr Pistorius to the toilet door when he shot through it, killing his girlfriend Ms Steenkamp?

The prosecution have already suggested - based on a preliminary analysis of the scene - that he was just 1.5 metres (4ft 11in) away, which would support their claim of premeditated murder, since at that distance the athlete would have ventured well into the bathroom and, one might conclude, could have known who was behind the door.

The defence maintains he was further back, cowering nervously at the entrance to the room, convinced a burglar (or burglars) was in his house.

Secondly, what was the vertical angle of the shot?

From this, the court will learn whether Mr Pistorius was on the stumps of his amputated legs, as he maintains, or wearing his "blades" as the prosecution has argued.

This is crucial. If it is proved that Mr Pistorius was lying in his opening statement, he will be in serious trouble - and the fact that he had time to put on his artificial legs will strongly support the notion of premeditated murder.

But if the forensics back Mr Pistorius up, then they will reinforce his story of a vulnerable man, unable to move quickly on his stumps, and anxious to protect himself and his girlfriend from suspected intruders.

Error of judgement?

Beyond those concrete questions, we start moving towards more circumstantial evidence - phone records which might, or might not, help to indicate an argument between the couple; the recollections of witnesses at the estate, who have reported hearing shouting; and character witnesses who may be brought in to try to prove that Mr Pistorius was a reckless, aggressive character, prone to sudden bursts of anger.

Image copyright AFP
Image caption Oscar Pistorius says he mistook his girlfriend Reeva Steenkamp for a burglar

At this stage, it is still too early to do more than speculate about any of this.

But the question that niggles me right now is this: What evidence does the prosecution have which pushed them towards the charge of pre-meditated murder?

Was it simply a tactic - to compel the defence to reveal their case in order to keep Mr Pistorius out on bail? Do the prosecution have an ace up their sleeve? Or were other factors at play?

You could argue that the state already had a confession, a victim and a killer.

There is no doubt that Mr Pistorius made - at the very least - a horrific, violently rash error of judgement.

The lesser charge of culpable homicide could still put Mr Pistorius away for a decade in jail.

So what did the prosecution find in those first few hours and days that made them confident enough to pursue a premeditated murder charge?

Nothing remotely conclusive emerged at the bail hearing - a fact that the hapless, and now fired, investigating detective, Hilton Botha, reluctantly conceded under cross-examination.

All these questions will no doubt surface during the trial.

Mr Pistorius himself is certain to take the stand. His performance, the forensic evidence, and the evidence of those first at the scene will be crucial; the character witnesses less so.

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