Dennis Richardson, who was described to the jury as the former ambassador to the United States, spoke of the time he has spent with Kapociunas, saying he was a "friendly, straight-forward" individual.

"In the capacity that I've known Vytas, he's always been ... an honourable person of integrity," he said.

Kapociunas' ACT Supreme Court trial resumed on Monday, and saw the defence call character evidence from those who have known him.

He is charged with three counts of sexual intercourse with a child outside of Australia.

It is alleged he molested a young girl three times in one day while in Spain, where his wife Jane Hardy was the Australian ambassador.

The girl told her mother that night that she had a secret and that she thought Kapociunas liked her, before indicating he kissed her on the mouth and on the groin area.

The Crown, represented by Carolyn Davenport, SC, allege he also touched her inappropriately while giving her piggybacks, although he is not charged with those acts.

In her closing submission, Ms Davenport told the jury the child's evidence had been consistent and adamant, to her mother, police, and the court. The girl's language, the Crown submitted, was not that of a child simply trying to get Kapociunas in trouble.

"They are the words that have the ring of truth to them, and the words of an innocent child," she said.

Ms Davenport asked the jury to consider what Kapociunas had confirmed in his own evidence; that he'd been alone in a bedroom with a young girl he didn't know well, that he'd blown raspberries on her tummy, and that he'd told her she looked "good enough to eat".

She suggested that was not a normal way to behave toward a child of that age.

In his closing, defence barrister Bernard Collaery described the complainant as an "imaginative" girl, who laughed during her police interview, but had never actually directly described Kapociunas kissing her genitals.

"What's truth, fantasies, lies to a child?" he asked.

"It's a matter for you."

He noted the child had never mentioned to her mother on the night of the alleged acts that Kapociunas had blown a raspberry on her stomach.

"There could be a completely reasonable explanation for all of this and it's gone completely off tangent," he said.

Mr Collaery said his client loved children, and had a clean record and a "throng" of witnesses to speak of his good character. He questioned why, all of a sudden, he would decide to abuse a child, while others were in the same home.

Kapociunas was said to have been fully cooperative with investigators, making himself available for an interview without a lawyer, and opening his home to police and Department of Foreign Affairs and Trade investigators. His actions were not those of someone with a guilty mind, Mr Collaery said.

Earlier, several witnesses spoke of growing up around Kapociunas, saying they never witnessed any inappropriate behaviour as children.

"I feel very safe in his company," one woman said.

Another said:

"I trust him with everything, it's almost like a second family to my family and me."

Mr Richardson said he had many interactions with Kapociunas and Ms Hardy during his time in Washington as ambassador.

He said his staff were required to conduct themselves in a "proper" manner, as were their spouses to a lesser extent.

"I know Vytas, in the capacity that I know him, has always been a person of integrity," Mr Richardson said.

The trial continues in the ACT Supreme Court on Tuesday before Chief Justice Helen Murrell.