Consultant psychologist Dr Alison Beck said that she had not wanted to be left alone with the defendant because ‘he was a danger to people’.
Referring to the tests carried out on Greenan, she added: ‘He is definitely a psychopath according to the scale.
Very few people would be this psychopathic.’ Greenan scored 34 out of 36 in the relevant test, a result which she said was ‘very rare’ because it was so high.
People with his disorder would often be detained in psychiatric institutions involuntarily.
Dr Beck, who was giving evidence for the defence, believes that the abnormality of Greenan’s mind substantially affects his ability to take full responsibility for Ms Burns’s killing.
If the jury accepts her conclusions, Greenan will be convicted of the lesser charge of manslaughter and not murder, which he denies.
Greenan admits trying to rape and violently attacking the 35-year-old nursery nurse from Newcastle with kicks and punches to the head in Paris Lane at around 1.30 am on 14 March.
She died in the General Hospital two hours later.
The Crown says that the accused’s judgment was more impaired by the 12 pints of lager he consumed on the day of the killing.
Earlier, the prosecution presented to the court a letter written by Greenan in La Moye prison to his mother days after Ms Burns’s death and intercepted by a prison officer.
In it, Greenan wrote: ‘I am sorry for what I have done and I no that sorry is not good enough.
I am just going to tell use what I think off myself.
‘Right, number one, it should not be that woman how is dead, it should be me, nobody else.
I am a low-life murder and a stinking dirty rapist and I need shot on the Head for what I have done.’ The Royal Court also heard that Greenan had tried to hang himself in La Moye prison after Ms Burns’s killing.
He had attempted suicide before, after being accused of sexually abusing a young niece and nephew back in Belfast, the court heard.
Dr Beck pointed out that Greenan’s condition meant that she believed he ‘blanked out’ when he committed the ‘frenzied attack’ on Ms Burns and, at the time, had little understanding of what he had done.
She added that he had lashed out because his disorder meant that he perceived an exaggerated threat during the attack, possibly when Ms Burns phoned her ex-boyfriend for help, even though she was not fighting back or struggling.
Dr Beck told the jury of the defendant’s past as learned through school reports, medical notes, her own interviews with him and other sources.
She said that he claimed to have been forced to leave his Belfast home after death threats from the IRA.
‘He described getting into a lot of trouble not just because of crimes that he perpetrated on individuals, but because by so doing he challenged the organisational powers of the paramilitaries,’ she said, adding that Greenan fantasised about being a gangster and related stories of fights with weapons he had been in to prove that he was ‘top dog’.
Greenan, the jury was told, tried to emulate his uncle Michael, who was a drug dealer and ‘hood’, but who would inflict violence on him.
He also told her of excessive drug-taking and the culture of violence he said he grew up in on the Poleglass estate in West Belfast.
Dr Beck said that his background, the way he responded to his actions and his criminal history suggested to her that he was suffering from ‘borderline’ and ‘anti-social’ personality disorders.
He could not differentiate between what he should, and should not, feel bad about.
Among the stories he told her, he said that he had once set fire to the bed he and his mother slept in and then got back in and pretended to be asleep.
An uncle, he said, came in and rescued them.
Greenan told her that he had stolen cars, committed robbery and burglary, been in numerous fights, drunk alcohol excessively most days, tried every drug except heroin and had consensual sex with a woman every day in Northern Ireland.
Dr Beck also used his overprotective relationship with his mother, whom he did not allow to bring men home because he was the ‘only man of the house’, and the lack of a father figure as reasons for his abnormality.
Assessments on Greenan when he was at school showed that he had difficulty obeying instructions from women, and he described the girls he slept with as ‘dirt bags’.
She said that he was manipulative, and listed other characteristics of a psychopath as being shallow emotionally, superficially charming and sensation-seeking.
Under cross-examination by Crown Advocate Cyril Whelan, Dr Beck admitted that there was little or no corroborating evidence of many of the stories Greenan told her of his exploits back home.
Advocate Whelan suggested that he could have lied to her and manipulated her.
She also conceded that psychology was not a precise science like chemistry and that she had not seen Greenan until eight and a half months after the killing.
Advocate Whelan drew her attention to her observation that the defendant’s past criminal activity had followed drink or drug-taking.
He said that Greenan had admitted that he attacked Ms Burns because he wanted to escape.
Media reports showed that Greenan had left his estate after a protest by neighbours who were sick of him breaking into their houses, rather than because of paramilitary threats.
Despite the tales of violence and fighting, Advocate Whelan pointed out that Greenan had no convictions for assault and had not resisted Filipe Henriques, the man who held him down as he tried to flee the scene of the killing.
The trial continues.
