Councils pursuing a zero-exclusions behaviour policy in schools risk ruining the life chances of other pupils, the Government’s behaviour tsar has said.

Tom Bennett, a Government adviser on behaviour, said a new charter introduced by Southwark Council in south London to minimise the number of exclusions could leave children exposed to “indignity and harassment”.

Southwark Council is the first borough in the country to ask schools to sign up to a policy of no exclusions, with teachers encouraged to take a “trauma-informed” approach to pupil behaviour.

Schools will sign up to an inclusion charter pledging not to exclude apart from in cases where other pupils are at risk of harm.

In the autumn 2021 term, there were no exclusions in Southwark schools, and the council hopes it will be the first borough in England with zero exclusions in the coming years.

Mr Bennett told BBC Radio 4’s Today programme that the exclusion rate in Southwark had been lower than the national average since 2012, with one year which he described as an “outlier”.

A council report in July 2020 into exclusions found Southwark had “largely followed the national trend of rising exclusions, with rates of exclusion doubling since 2012/13”, and that as of 2017/18 its exclusion rates were above the London average, although lower than the average rate nationally.

Mr Bennett said: “What the charter clearly states is that for any behaviour short of the most extreme behaviours like knife crime and so on, this school should probably consider not excluding

“That sounds fine in principle but there’s lots of misbehaviour short of criminality which absolutely harrow and ruin the life chances of children in schools.

“All children have got the right to a safe, dignified learning which is calm and staff do too, and exclusions are a necessary part of that process.”

He said schools which choose not to exclude a pupil could expose other children to “days and days of indignity and harassment”.

Southwark Councillor Jasmine Ali said that in 2018, the borough had seen exclusions were rising sharply, with 49 exclusions.

“Now that’s quite a lot of children,” she said.

She said the council subsequently formed a strategy with partners from the safeguarding board and schools, and that currently exclusion rates had already fallen to 10 children.

“I wouldn’t have thought this would have been so controversial,” she said, adding that the council’s aspiration is for “100% inclusion of children in education that keeps them safe and enables them to flourish”.

Ms Ali said she was “disappointed” by Mr Bennett’s comments, adding that a child facing exclusion has “an unmet need”.

She said exclusions are akin to pressing a “nuclear button” and the council is providing wraparound support for vulnerable children to prevent this.

The charter commits to a multi-agency approach focused on early intervention with pupils.

Schools signing up to the charter must pledge not to “encourage parents to explore elective home education as a resolution to issues with inclusion” – widely seen as a form of off-rolling.

The charter says managed moves between schools may offer pupils a “fresh start”, but discussions about a possible move for a pupil must not take place informally.

It adds that it recognises “there are rare instances where exclusion is unavoidable to safeguard children”.