A well-known artist having affairs with his students says he didn't know one was underage until he became the subject of a police investigation.

The man, whom the Herald cannot name due to court suppression orders, is on trial before a jury and Judge Brooke Gibson in the Auckland District Court.

The trial is in its third week.

The man is charged with six counts of rape, five of indecent assault, five of unlawful sexual connection, two of sexual connection with a young person, and one of an indecent act on a young person.


He is also charged with assault against a student using a belt. He denies all the charges.

Today, the artist, whose works are understood to be hanging in well-known galleries and offices, gave evidence in his own defence.

He said he never forced any of his students to have a sexual relationship with him.

The artist is accused of violating four women, aged 14-18, during 2014 and 2015 at his private Auckland studio.

Defence counsel Phil Hamlin has said his client categorically denies any touching was inappropriate or without consent.

The artist "believes honestly" that when there was a sexual relationship it was consensual, he said.

Hamlin asked the artist today if he forced himself on his students.

"I did not," the man replied.

At the start of the trial, Crown prosecutor Dale Dufty told the court that the artist said to the students to "pretend that nothing had happened" and "not to tell anyone or he would go to jail".

"Did you say to [your student] that you knew it was wrong and you could go to jail?" Hamlin asked.

"No, I did not," the artist said.

He said it appeared his student's were "happy" to be having sex with him and didn't display any negative attitude towards the physical relationships.

He said he would discuss "Greek goddess" artwork with his students and how he was able to interpret the emotion of another artist by what colours and brush strokes they used.

The artist also said he didn't know exactly how old his students were.

"I didn't exactly know how old they were, I just thought they were around 17-18," he said.

He added that he only learnt one of his students, whom he was having an affair with, was underage after criminal allegations were made to police.

The artist also said he never used a belt in any way to harm one of his students.

Under cross-examination, Dufty asked the artist if he would simply tap his students on the shoulder for them to follow him into his private studio.

The artist agreed and said he was sexually attracted to the teens.

Dufty said he conjured up "fantastical stories" to tell his students, including that he was part of a "mind-control experiment in Switzerland".

"Most of the stories you told your students were made up, weren't they?" The prosecutor asked.

"Some stories were originally not the true story," the artist replied, adding that he never shared the mind-control story.

"You never thought it was inappropriate, what you were doing with the students?" Dufty asked.

"When you have a love for painting, you never ask why," the artist replied.

One of the teens has said the artist told her he was "taking [her] on a journey, you need to know that and be prepared".

But, the artist said the expression was not a reference to sex.

The trial continues.