Several principals had spoken to him of fears held by school managers and teachers about being charged with assault or being the subject of a Teacher's Council complaint if they became involved, Walsh said.
"Clearly they're looking for answers and I think the working group's an opportunity to discuss those and come up with appropriate guidelines," he told the Herald on Sunday.
"The study's being conducted at the moment, they've got a researcher visiting schools to look at best practice, they've got the legal division of the [Education] ministry and Crown Law looking at what's lawful in this area, and then they're looking at best practice overseas.
"I think it's a very good initiative, and it's important to stress it doesn't happen a lot, we're dealing with the extreme end of behaviour."
While police would be called to serious incidents, including those involving weapons, Walsh said it was important staff had the skills to deal with a violent student before authorities arrived.
Ministry of Education head of sector enablement and support Katrina Casey said the guidelines would focus on seclusion to manage the worst incidents.
Teachers would be given scenarios to show how to respond when faced with a situation in class.
The working party includes representatives from the Ministry of Health, Education, Child, Youth and Family and educationists.