The lawyer representing former Malaysian diplomat Muhamad Rizalman Ismail told the High Court in Wellington today that "bad forces" could have affected his client.

Queen's Counsel Donald Stevens said Rizalman's wife had described that her husband faced a slew of health and behavioural problems when he took up his post as defence attache in Wellington.

These issues, the lawyer said as reported by the New Zealand Herald , allegedly included "hallucinations", memory loss and heart palpitations.

"His behaviour changed. Some days he was okay, other days he was not. And he would frequently have very little memory of the events that took place on the days he was not okay."

“Rizalman would sleep at his desk for no reason, and would sometimes sit in the same place for hours, disengaged and at times in a 'perpetual daze',” the lawyer informed the court.

Stevens said the military attache's wife was therefore worried that her husband was suicidal.

"She describes how she hid the knives in the house. So the evidence (shows) Rizalman's behaviour continued to deteriorate in the period leading up to the May 9 (the day of the incident).

"He said bad forces were affecting his mind. In his abnormal state of mind, he failed to appreciate that it was inappropriate to enter a strange woman's bedroom without his trousers or (underpants) on," Stevens said.

"There can be little doubt that Mr Rizalman was in an abnormal mental state."

The lawyer was submitting today before court which was deliberating on Rizalman's state of mind and whether synthetic cannabis played a role leading to the assault on a woman.

'He wanted to talk about his problems'

Rizalman was reported to have admitted to indecently assaulting Wellington woman Tania Billingsley at her flat in May 2014 but the hearing continues as he disputes certain aspects of the Crown's case against him.

He said he saw Billingsley, 22, in Brooklyn and believed she'd given him a look that gave permission for him to follow. He says he wanted to talk about his problems.

Last week, Rizalman admitted to smoking cannabis, buying legal highs and believing in black magic.

However, he denied defecating outside Billingsley's house, to cast a spell on her.

The former military attache alleged he had defecated due to diarrhoea and entered Billingsley's flat without his pants or underpants to clean himself up, but the Crown (prosecutor) alleged the motive was sexual.

Rizalman also did not admit to smoking the legal highs (substances) and claimed at the time of the alleged offence, he was suffering from stress due to work pressure.

'Could have overpowered'

Another contentious issue, as reported by the Herald , was the existence of any possible mental illness following an earlier medical assessment that diagnosed Rizalman as having 'mixed depression and anxiety'.

The case is being presided by Justice David Collins, who wanted more details regarding Rizalman's two visits to a Johnsonville general practitioner before May 9 last year.

Stevens said today that Rizalman's Malaysian diplomatic colleagues noticed him behaving strangely for weeks before the incident.

Before the indecent assault incident, a Malaysian colonel had considered sending Rizalman back to Malaysia, the lawyer added.

Stevens said it was understandable, but mistaken, for Billingsley to fear the worst.

"She thought she had to get this man out to save herself,” he said, adding that Rizalman, with his military background and training, could have overpowered the young woman if he had wished to.

"Instead, he allowed himself to be pushed backwards, out of the room, all perfectly consistent, in our submission, with Rizalman's explanation of why he went into the house (to allegedly make the emergency toilet stop)."

Justice Collins said he will deliver his judgment next week.