Oscar Pistorius trial: Live updates as judge rules whether athlete should be sent to psychiatric unit for assessment

9:14 am

The witness went on to say Pistorius' reaction should be viewed in light of his physical vulnerability, and his general anxiety disorder.

Judge Thokozile Masipa says the law does not define mental illness, but it would be "unwise" for the court to attempt a diagnosis without help from experts.

She says a doubt has been created that the accused may possibility have another defence relating to his criminal responsibility - there may be diminished criminal responsibility.

She says Dr Vorster's evidence has not been challenged, and can only be by other psychiatric experts.

9:09 am

The judge is now talking about Dr Vorster's evidence, which triggered the application.

Dr Vorster said Oscar was "hyper-vigilant", and has a long history of generalised anxiety disorder that appears to be increasing with time.

She says that when threatened, Pistorius is more like to respond with a "fight" response, because "his capacity to flight was compromised".

9:05 am

She says the crucial part of the relevant legislation is that it says that if "due to mental illness or mental defect the accused might not be criminally responsible, a referral is in order".

She says the accused may not have raised the issue that he was not criminally responsible at the time of the incident, but evidence given on his behalf clearly raises the issue and cannot be ignored.

9:01 am

Judge Thokozile Masipa is now delivering her ruling.

She says "strangely", the prosecution's application is opposed by the accused.

8:59 am

Almost half an hour late, but we're about the get under way.

The judge has just entered the court room.

8:48 am

We're still waiting for the judge to arrive and announce her decision, but Pistorius' lawyer and family members look solemn and concerned.

The athlete's uncle, Arnold, let out a long sigh after speaking with Barry Roux, who is now chatting with Oscar again.

8:41 am

Reeva's mum June Steenkamp is also here, wearing a badge with her daughter's picture on it.

Pistorius' barrister Barry Roux has just entered the court room, and is speaking quietly to the athlete.

8:33 am

Oscar Pistorius has arrived at court to hear if he will be sent to a psychiatric unit for the next 30 days.

Lawyers in the case have been called into chambers with Judge Thokozile Masipa.

8:26 am

If the prosecution's application is successful, the trial will be adjourned until after Pistorius' stay at a psychiatric hospital.

If however the judge decides he should not have an assessment, proceedings will resume and Roux will call his next witness.

That is expected to be Pistorius' orthopaedic surgeon.

8:23 am

Pistorius's chief lawyer Barry Roux says Pistorius should not be sent for 30 days of psychiatric evaluation, and that he wants to call another witness to continue evidence.

He said at the start of the athlete's defence that the double amputee's vulnerability and disability was at the centre of his case of a mistaken killing.

But psychiatrist Ms Vorster only met Pistorius this month, prompting the prosecution to question whether the timing of her late entry to the stable of witnesses signified a change in tactics by the defence.

7:46 am

Making his request for Pistorius to undergo an evaluation, Mr Nel questioned why the defence had asked psychiatrist Merryll Vorster to testify on the Olympic runner's behalf.

He suggested that the trial is not going well for Pistorius and his lawyers are floating the idea that a disorder contributed to Reeva's shooting and that therefore Pistorius bears less responsibility for her death.

In asking for another professional evaluation of Pistorius's mental state, Mr Nel appeared to be trying to ward off any attempt by the defence to say Pistorius should be treated favourably by the court because of a mental condition linked to his disability.

6:50 am

Oscar Pistorius will find out this morning whether he has to spend 30 days under psychiatric evaluation as part of his murder trial.

The chief prosecutor in the case has asked that the runner be put under observation, after an expert witness testified that he had an anxiety disorder.

Gerrie Nel made the request after noting the psychiatrist for the defence said the disorder could have played a role in the fatal shooting of Reeva Steenkamp.

Mr Nel acknowledged that an evaluation of the Blade Runner's state of mind will further delay the trial, which has already over-run by a number of weeks.

Judge Thokozile Masipa will rule on the application at 8.30am BST this morning.