He was in Dunedin to address the Mirror Services’ 30th anniversary symposium, and said "genuinely hearing" what young people had to say was the starting point for his work.
Children should be consulted when tackling the issues facing them, which included housing, mental health, Oranga Tamariki and school governance, Judge Becroft said.
"Listen to children and young people. There is wisdom there [and] we seem to be frightened of it in New Zealand."
The mental health of young people was identified as a growing area of concern, particularly for minority groups such as Maori, disabled, and LGBTIQ.
Speaking after his talk, Judge Becroft said children’s mental health was a "growing, profound problem".
"I’ve called it one of the emerging issues of our time for New Zealand."
He said it was exactly the sort of issue children could help to tackle, and that they wanted to talk about it.
"We need to create the environment where they can[talk] and they feel able to do it."
In his address he said he had seen first hand the effect that involving children could have on decision making, and gave the example of an inter-college football club he was involved with.
They had a problem with boys leaving the sport in year 11, and decided to add some of the players to the board.
Based on the advice of the young footballers they changed from selecting teams based on skill, and instead let the children choose their own teams so they could continue to play with their friends.
"We went from five teams to 21 teams and we are now the largest football club at an all boys school around."
Judge Becroft said that Dunedin was well placed to tackle children’s issues and that Dunedin was "blessed and privileged" to have organisations like Mirror Services.
"They and other like organisations in Dunedin are a powerful voice for change."
He said Mirror was a good example of an organisation that was genuinely child-focused, and offered "warmest congratulations" for reaching its 30th anniversary.
Mirror Services provide counselling and treatment programmes for vulnerable children in Otago and Southland.
