A Malaysian military man who defecated outside the house of a woman he followed home was likely to have lied about his drug use, mental health experts have said.

Muhammad Rizalman Ismail, 39, had pleaded guilty to indecent assault on Monday, the morning his trial was due to begin in the High Court at Wellington after following Tania Billingsley to her home on May 10, 2014.

Two other charges of assault with intent to commit sexual violation and burglary were discharged by Justice David Collins.

Instead a disputed facts hearing was heard on Friday with Rizalman giving his side of the story publically for the first time.

He told the judge that he had only wanted to be friends with her and talk to her about his problems but accepted he had gone into the house without any trousers or underpants.

The Crown case is that Billingsley had been home alone watching a movie in her bedroom when Rizalman came in without his trousers and underwear.

Billingsley looked up and saw him wearing only a shirt and naked from the waist down. She screamed at him to leave. Rizalman put his hands on her shoulders but she managed to push him into the living room then out of the flat before locking him out.

She then locked herself in the bathroom and called police. A flatmate's boyfriend arrived home and challenged Rizalman who was still outside the front door.

Rizalman began walking away but was stopped down the road by the police.

Rizalman had left New Zealand without facing trial after Malaysia invoked diplomatic immunity, in the belief it did so with the New Zealand Government's blessing.

He returned after extradition hearings were filed in Malaysia.

At the time of the attack he had been working at the Malaysian High Commission as a staff assistant to the Malaysian defence advisor.

Billingsley waived her right to name suppression.\

Black magic

Rizalman admitted to Crown prosecutor Grant Burston he believed in black magic and knew of a spell about having a woman fall in love with you if you defecated outside her house.

He also said he thought a superior officer had put a spell on him.

Rizalman agreed he had not told police, or others, about pooing outside the house because he was too embarrassed.

"So the only time you have had an emergency defecation just happens to be in those 30-40 minutes waiting outside this young woman's house?" Burston asked.

"Yes," Rizalman said.

Burston said: "It was the reason you took off your belt and lowered your trousers and underpants outside this young woman's front door on the patio.

"It was more about black magic than about having to go to the toilet in an emergency."

Rizalman said no, but agreed he had bought synthetic cannabis from a Cuba St shop the week before and followed another woman the day before, as well as going to Mermaids Bar.

He told Burston Billingsley had given him a signal and wanted to befriend him which was way he had followed her home.

He said in Malaysian culture if a woman smiled at you she wanted to get to know you better.

Psychologist Professor Graham Mellsop told the judge Rizalman had scored high on the lying and faking scales in a report, meaning he did not always tell the truth and suggested he was exaggerating his symptoms.

He said the only logical conclusion was his problems had come from drug ingestion.

Mellsop said he accepted there were behavioural changes, like Rizalman forgetting the words of a prayer he said five times a day but he attributed them to more regular substance ingestion.

Rizalman's, lawyer Dr Donald Stevens QC, challenged Mellsop's opinions saying Rizalman had been suffering from anxiety and others had seen the changes in his behaviour.

However Mellsop said he did not think Rizalman was in a state of confusion on the day of the incident since he was subsequently able to give detailed explanations of what he said had happened.

Consultant forensic psychiatrist Dr Justin Barry-Walsh also said he felt Rizalman had not been truthful about his drug intake.

The judge has adjourned the case for a week to hear submissions from the lawyers and make a decision.

- Stuff

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