Key Points:

A disgraced Gisborne music teacher accused of sexually abusing his students developed relationships with students he gave private lessons to, says his former principal.

Stephen Michael Shone was remanded in custody on one charge of sexual violation by unlawful sexual connection, 10 charges of indecent assault and one of unlawful sexual connection with a girl aged 14.

The girls, aged between 13 and 16 when the offences were committed, all gave evidence in the Napier District Court earlier this week.

Former Gisborne Intermediate School principal Bruce Popham said Shone got on well with other staff, ran a diverse music programme at the school and gave no indications of any inappropriate behaviour.

He was "able to inspire the students to new levels in music".

"The children who were taught by him were definitely advantaged and I had no reason to be concerned," said Mr Popham.

"There was no sixth sense or any indications he gave me other than trying to promote quality music."

But, he said, because of a lack of music teachers of similar quality in Gisborne, Shone had a lot of pupils who would see him after hours.

Detective Sergeant Steve Smith of Gisborne CIB said Shone's offending came to the attention of the police in March last year.

Mr Smith said Shone, who has been prominent as a multi-talented instrumentalist in the Gisborne music scene since his early teens, was "still highly thought of" in music circles in the community.

But his offences, which date back to 2002, were a "clear breach of his personal authority and trust".

"It's typical of these types of offences, they're done in private and there are no independent witnesses or anything like that," he said.

Asked why it took so long for Shone's offences to be revealed, Mr Smith said: "It's more a comment on how he went about his offending".

Shone's lawyer, Adam Simperingham, told the Weekend Herald Shone had changed his earlier plea to guilty after the Crown withdrew charges of sexual violation.

"He'd always maintained that sexual incidents had been consensual," he said.

Earlier this week the jury was told how Shone groomed his victims and developed boyfriend-girlfriend relationships with at least three of them and committed offences with the girls at various locations.

Over one month last year Shone exchanged 1547 text messages with a complainant. He will be sentenced in Gisborne on September 29.