The investigation by Geelong detectives follows a string of recent allegations against several teachers who, it is claimed, engaged in inappropriate conduct at the exclusive school starting in the 1960s.

Several former students told Fairfax Media that Whitcroft was accused of groping a male student in a dormitory bed in 1993, before he was sacked by the school and asked to vacate his on-campus accommodation.

The allegations were never reported to police at the time and the school failed to explain Whitcroft's sudden departure to students.

Past boarders from the college said Whitcroft would regularly invite students to his unit, where he would allow them to smoke and sometimes offer massages.

David Whitcroft at the County Court in Melbourne. Photo: Jason South

He is understood to have massaged up to a dozen boys.

"Unaccompanied boys would go to this guy's apartment, disrobe to their underwear and be massaged.

"Looking back on it, I can't believe that was going on at the school and no one stopped it," one former student said.

Another student said it was: "flat out grooming, we just didn't know it at the time.

"I have grave fears for one bloke, who was particularly vulnerable and spent a lot of time at his [Whitcroft's] place."

Dr Hugh Seward, chair of the Geelong College Council, denied any report of a sexual assault had been received by the school at the time, but confirmed Whitcroft's role as a duty master had been terminated when he defied instructions not to massage boys.

"The college recognises that if this type of conduct was intended to facilitate a child's involvement in a sexual offence, it could be considered grooming, which is now a criminal offence," Dr Seward said.

"While the actions of the principal indicate he was uncomfortable with Mr Whitcroft's behaviour, he did not have evidence of such an intention or a criminal offence to report."

Dr Seward confirmed the college had co-operated with the Geelong Sexual Offences and Child Abuse Investigative Team, which is understood to have spoken with several past teachers.

The school has also appointed an independent facilitator to provide counselling, along with policies and procedures to protect students from abuse.

After leaving Geelong College in 1993, Whitcroft is understood to have relocated to Rockhampton for a time, but he is known to have returned to Melbourne and worked as a rowing coach at other private schools.

On May 3, Whitcroft now 68, was sentenced to 18 months in prison, plus a two-year community correction order, after pleading guilty to five charges of sexual penetration of a 14-year-old boy at the Sunshine Boys' Hostel in 1982.

Whitcroft was employed as a social worker. He admitted taking his victim to a farm near Torquay, where the vulnerable teenager was plied with marijuana and scotch, offered naked massages, and abused.

Whitcroft was told by Judge Duncan Allen his crimes were towards the severe end of the scale, because of his "position of trust, the ongoing nature of the offending, and the impact on the victim".

Police recommend anyone who is a victim of sexual abuse should seek counselling at the Centre Against Sexual Assault and speak with a specialised detective at their local Sexual Offences and Child Abuse Investigation Team.