The prosecution in the trial of South African Olympic athlete Oscar Pistorius has formally requested that he undergo a mental observation.
Prosecution lawyer Gerrie Nel made the application after forensic psychiatrist Merryll Vorster said the double amputee was "a danger to society".
Judge Thokozile Masipa said she would announce her decision on Wednesday.
Mr Pistorius denies intentionally killing his girlfriend Reeva Steenkamp on Valentine's Day last year.
He says he accidentally shot her through the toilet door in a state of panic, mistaking the 29-year-old model and law graduate for an intruder.
The prosecution accused the defence on Tuesday of changing its plea - from putative self-defence to a psychiatric disorder.
Mr Nel said that a "psychiatric evaluation was essential" and it was in the interests of justice for the accused to be referred.
The defence is vigorously resisting the prosecution move, which it argues is "manifestly absurd".
Dr Vorster told the court earlier that she would not say that Mr Pistorius had "a mental illness" and that he was "still able to function at high level as an athlete and still able to socialise".
But she said that people with Generalised Anxiety Disorders (Gads) like Mr Pistorius probably should not have firearms.
She said that Gad would not "render you unfit to stand trial".
The BBC's Andrew Harding says that the psychiatrist shored up the defence's argument that Mr Pistorius does not need mental evaluation.
On Monday she said that the athlete had had an anxiety disorder since childhood and was "anxious" about violent crime.
His actions on Valentine's Day last year "should be seen in context of his anxiety" and would have been different from "normal, able-bodied person", she said.
If the prosecution request is granted, Mr Pistorius may spend up to 30 days in a state mental health institution for observation and assessment of his mental health.
Court sources have indicated that it is unlikely the judge will grant the prosecution its request, our reporter says.
There are no juries at trials in South Africa, so the athlete's fate will ultimately be decided by the judge, assisted by two assessors.
If found guilty, Mr Pistorius - a national sporting hero dubbed the "blade runner" because of the prosthetic limbs he wears to race - could face life imprisonment.
If he is acquitted of murder, the court must consider an alternative charge of culpable homicide, for which he could receive about 15 years in prison.
Mr Pistorius said in his statement at the start of the trial that he woke in the early hours and walked on his stumps to the balcony, pulled in two fans, closed the sliding door and drew curtains. He said that shortly before he had spoken to Reeva, who was in bed beside him.
He said he rejected prosecution claims that a witness heard arguing coming from the house before the shooting.
2. Bathroom window×
Mr Pistorius said he heard the bathroom window sliding open and believed that an intruder, or intruders, had entered the bathroom through a window which was not fitted with burglar bars.
"Unbeknown to me, Reeva must have gone to the toilet in the bathroom at the time I brought in the fans," he said.
Mr Pistorius said he approached the bathroom armed with his firearm, to defend himself and his girlfriend, believing Ms Steenkamp was still in bed.
Both sides agree four bullets were fired. Ms Steenkamp was hit three times.
Mr Pistorius said he fired his weapon after hearing a noise in the toilet which he thought was the intruder coming out of the toilet to attack him and Ms Steenkamp.
He said he was in a fearful state, knowing he was on his stumps and unable to run away or properly defend himself.
Mr Pistorius said he rejected claims that he was on his prostheses when he shot at the door.
A witness told the trial she woke to hear a woman screaming and a man shouting for help. She said that after the screams she heard four shots.
Mr Pistorius said he went back to the bedroom after shooting at the toilet door, still shouting for Reeva. Lifting himself up onto the bed, he felt over to the right hand side of it and noticed Ms Steenkamp was not there.
Mr Pistorius said this was when he realised she could have been in the toilet.
5. Toilet door×
Mr Pistorius said he went back to the bathroom but the toilet was locked, so he returned to the bedroom, pulled on his prosthetic legs, turned on the lights before bashing in the toilet door with a cricket bat.
Forensics expert Johannes Vermeulen told the court that the height of the marks on the door caused by the cricket bat suggest Mr Pistorius was on his stumps at the time.
6. Emergency calls×
Mr Pistorius's defence team say he then called security at the gated housing complex and a private paramedic service before carrying Ms Steenkamp downstairs.
A security guard claimed it was the other way round, and he had called Mr Pistorius first after reports of gunfire. However, phone records shown to the court revealed Mr Pistorius called the estate manager at 3:19am, a minute later he called the ambulance service and at 3:21am he called estate security.
A minute later he received an incoming call - estate security calling him back.
According to police phone expert Francois Moller, Mr Pistorius called his friend Justin Divaris a short time later and just after 4:00am he called his brother Carl.