"May I remind parents and boys that hair must be above the collar and not so long over the eyes to be a nuisance when studying or playing sport. Dyed hair or extreme hairstyles are not permitted."

A teacher from one of Melbourne's other top boys private schools, who spoke on the condition of anonymity, told The Age haircut policies were supposed to teach students "discipline".

"We get told it's so the students learn to look respectable for job interviews when they leave school," the teacher said. "There's also an aspect of that military-style uniformity too and maintaining the school's image."

The teacher's employer, like many other private boys' schools in the state, regularly sends students with inappropriate hairstyles to get haircuts during school hours. Parents must then reimburse the school for the cost of the haircut.

A student from Trinity Grammar headmaster Dr Michael Davies' previous employer St Kevin's College, where he was deputy headmaster, contacted The Age, saying Dr Davies sent students to get haircuts during school hours when he worked at the Toorak school.

Mr Brown was sacked for his actions which the school council said were "inconsistent with community expectations". But his supporters say his dismissal was politically motivated.

A woman who said she was the aunt of the boy whose hair was cut told a school meeting on Friday night that the family did not want Mr Brown to be sacked for his actions, which other students said the long-time staff member had done before.

Schools are given the power to set and enforce dress and appearance standards under the Equal Opportunity Act (2010).

In a statement sent to The Age, Independent Schools Victoria chief executive Michelle Green said they had no control over haircut policies of particular schools.

"All schools, regardless of whether they are independent, government or Catholic, can apply reasonable standards of dress and grooming for their students," Ms Green said.

"These standards vary widely, depending on the philosophy of the school. Parents and students usually agree to accept the standards when enrolling."

Like the Trinity Grammar students who do not want Mr Brown sacked for his actions, students largely accept and abide by such policies because it is clearly communicated to them throughout their time at the school as a condition of their enrolment.