A member of the Dilworth Old Boys Association has labelled the handling of a recent race-related incident "a disgrace" that exposes the Dilworth brotherhood as a sham.
Four alumni have had their suspensions from the association lifted after they made comments about the school's ethnic make-up, saying it was "unbalanced".
The Dilworth Old Boys Association did not agree this was the case, suspending the men before lifting those suspensions at the Association's annual general meeting on Saturday.
The men, who had threatened legal action if their suspensions were not lifted, were former headmaster Murray Wilton, another former headmaster, Denis Bradburn, former association president John Simpson and a member of the association's council, Sandy McNeur.
At Dilworth, Maori make up 24 per cent of the student population, Pasifika boys 38 per cent, European 27 per cent, and Asian 7.5 per cent, with 3 per cent of students listed as "other".
• Old Boys suspended for race comments on school
The school has traditionally provided schooling for boys from poor backgrounds. It is a boarding school which charges no fees and offers scholarships for some boys.
The suspensions were lifted on Saturday following "11th hour" negotiations at Dilworth Old Boys Association annual general meeting, wrote member Warren Wilton on a private Facebook page.
Mr Wilton is Murray Wilton's brother.
The meeting was "attended in unprecedented numbers" this year due to the controversy, he said.
In a post headed "The Dilworth brotherhood only goes so far", Mr Wilton lashed out at the association over its handling of the incident, saying they had effectively suspended his brother, the group's head patron, by voting not to fill the position for the next year.
"The humiliation of Dr Wilton, who has given more than half his 80 years to Dilworth School and and its Old Boys Association, is a disgrace and shows the 'Dilworth brotherhood' is a sham," he wrote.
"Far from settling this issue in the spirit of brotherhood, the removal of Dr Wilton as patron divided the old boy community."
Mr Wilton said there was now "the very real prospect" a rival old boys' association would be established to challenge the board's decisions.
While the four men represented a group of old boys who saw the school's current makeup as unbalanced, the board rejected those allegations.
"The board will continue to observe the Founder's wishes as expressed in the will by granting scholarships to applicants from straitened circumstances, with no consideration to race or ethnicity," chairman Jon Wain posted on social media.
"The board rejects recent allegations that it has acted contrary to the terms of the will, and is disappointed that recent events have detracted from the excellent work done by the school to foster an all inclusive, multi-cultural learning environment."