One Waikato teacher is under investigation by the New Zealand Teachers Council for sexual misconduct while almost 50 others have been convicted of various charges over the past two years.
Figures released under the Official Information Act show, of the 48 convictions for the region's teachers since 2010, 30 were for alcohol and drugs, five for violence and one each for sexual and pornography offences.
As of July this year, there had already been 17 convictions handed down to Waikato teachers.
There were also 38 cases of teacher misconduct investigated, including five for sexual misconduct, four for violence and dishonesty and 22 for what was defined as "other".
However, only four of these teachers had their registration cancelled, eight faced censure and, in 33 cases, no further action was taken.
Education lawyer and Secondary Principals' Association president Patrick Walsh said the convictions were "extremely serious and very disappointing" and called for more rigorous vetting of school staff to reduce the number of teachers who "fall through the cracks".
"I think any time a teacher is involved in a criminal offence is a serious matter because they're in a position of high trust with children and they are supposed to be role models for young people."
In September 2010, Putaruru College teacher of 30 years, Roger Bruce Radford, was convicted of downloading more than 3000 images of naked girls, some as young as eight, to a personal computer. Radford told police at the time that the photos were for his own sexual pleasure. He was sentenced to two years' intensive supervision and 250 hours' community work.
Also in 2010, former Putaruru College physical education teacher Ryan Emery was banned from teaching for life after having an affair with a 16-year-old female student in 2007.
And the Times can reveal that another Waikato teacher is currently under investigation for sexual and "other" misconduct following a complaint to the Teachers Council by their employer in March.
Mr Walsh said the cases were "hugely damaging" for the profession and diminished the trust of parents and the public.
"That's why a hard line has to be taken against them; [they need] to be weeded out and prevented from ever entering the classroom again," he said.
"Above all, parents should have an expectation that their children that they send off to school each day are going to be safe."
Teachers Council director Peter Lind said greater co-operation between agencies, such as police and corrections, was being worked on, but employers needed to be more vigilant.
"Accepting somebody's CV, or accepting somebody at face value, even if it's a short-time position, poses a risk."
He said there had been a slight increase in the number of teachers convicted since 2005, but it accounted for a small percentage of the workforce.
- © Fairfax NZ News