Teenagers who commit sexual violence should have mandatory treatment, a counsellor who works with sexual offenders says.
His comments come after a group of schoolboys were given warnings by police after they performed crude acts on drunk girls and put pictures online.
Secondary Principals' Association executive member Patrick Walsh said the case involved senior boys from a secondary school he could not name.
He said the students took explicit photos of themselves with drunk girls, including some who were hardly conscious, before posting the pictures on a private Facebook page. He was concerned the boys only received warnings from police.
Russell Smith is the co-director of Korowai Tūmanako, which provides therapeutic services for children, adolescents with sexually harmful behaviour and adults who have sexually offended against children. He is also a clinician and worked for the service for 11 years.
Mr Smith said the type of behaviour engaged in the schoolboys was becoming more common and a slap on the wrist was not enough.
"This Facebook thing, it's like part two of the Roastbusters. I think it needs more than just a warning. I think there needs to be some enforced mandatory counselling and then at least they're on the radar, and should those young people reoffend in future, you [sic] can be charged and they can bring that historical harm forward."
The so-called Roastbusters case involved a group of teenage boys who boasted online about having sex with drunk girls, some as young as 13.
Mr Smith said young men need to get the message that such behaviour was unacceptable.
"We all know what happened with Roastbusters... but I daresay that those boys may not have got any support around the harm they've caused.
"With the young people who've done harm that I've worked with, they're certainly sorry for their actions, but primarily a lot of them are sorry because they got caught. It's more likely that they could have continued with that behaviour if it had gone unchecked. "
He said young people's behaviour could change with treatment. "We've got to remember that these young people are developing and extending their boundaries developmentally and extending their behaviours sexually and that increases as they grow up." Young men only become aware at age 21 or 22, and at 14 or 15 years old did not have the developmental maturity or empathy to understand the consequences of their actions.
Mr Smith said pornography and and social media were responsible for much of the early formation of harmful sexual behaviour and attitudes.
"We're in a society now where soft porn today used to be hardcore porn 20 years ago. Hardcore porn is quite serious, so when young people get exposed to that, pornography lights up the brain of a young person - or like anyone - it arouses them because it stimulates the brain in a way that it's not supposed to be [at that age].
"So we're getting more young people exposed to it and more young people who are practising harmful sexual behaviour on their peers.
"I've worked on cases where we've had a couple of five-year-olds acting out sexually on each other under the table at a primary [school]. It just begs the question about the environment and what they've been exposed to in their home. The media is rampant with pornography."
The police said they had spoken with the Secondary School Principals' Association over its concerns around the group of senior schoolboys.
Mr Walsh said the boys' behaviour was unacceptable and there needed to be better help from the police.
In a statement, police said they now had a better understanding of Mr Walsh's concerns after speaking with him.
They were looking to work more closely in a partnership with the association to make sure students felt supported and safe, they said.
They could not comment on the specific case, but said they took all allegations of sexual misconduct and assault very seriously.