Less than 10 per cent of the 474 young people who appeared in Tauranga Youth Court over the past three years were convicted of a crime.
The Ministry of Justice figures, released under the Official Information Act, showed that last year there were 141 youth court appearances in Tauranga, slightly up from 138 in 2011, and significantly down from 195 in 2010. Of these, 42 were convicted of a crime.
Tauranga police officer in charge of youth services Nga Utanga said youth court appearances had dropped in the Western Bay of Plenty due to hard work by police and the community.
"Some of the core lessons that we learned ... were the amount of repeat offenders, so there's a lot of focus being put on identifying them."
Police had also been working more closely with schools, setting up "truancy action groups" that identified children deemed to be at risk, Mr Utanga said.
The most common youth offences in the Western Bay were shoplifting and wilful damage, he said.
Nationally, 3015 people appeared in Youth Court last year, with 198 convicted.
The figures showed youth court appearances had been dropping in recent years.
There were 3579 Youth Court appearances in 2011, down from 3942 in 2010.
The majority of appearances last year were by males aged between 14 and 16 (2430). However, the figures showed 564 female youths also appeared.
Principal youth court Judge Andrew Becroft said that unlike adult offenders, around only 20 per cent of youth offenders arrested by police were taken to court. "The other 80 per cent are not let off, but they're dealt with by police firmly, promptly, creatively, in the community."
Most youth offenders police dealt with "aged out" and did not reoffend, Judge Becroft said.
District courts general manager Tony Fisher said there were a number of possible outcomes after a child or young person appeared in youth court and admitted to the charge or, had the charge against them proven.
Under the least serious outcome, police could decide not to take the case any further - the same as if the youth had never been charged.
At the most serious end of the scale, the youth's case could be moved to the district court for sentencing.
Other possible outcomes included a "conditional discharge" - where the youth was let off unless they broke the law again within a certain time, reparation, alcohol or drug rehabilitation, community work, or be placed under the care of Child, Youth and Family.
The youth court could also order the child's parent or guardian to attend a parenting education programme.
Aside from a district court sentencing, the outcomes were noted on the youth's record of behaviour, but did not count as criminal convictions, Mr Fisher said.
"They do not affect the child or young person's chances for a job or overseas travel."
Youth justice advocate JustSpeak spokeswoman Danielle Kelly said most New Zealanders would be surprised how variable prosecution decisions were for young people.
"Locally tailored approaches are a valuable part of our justice system. However, it is not fair if a young person in Auckland may be denied alternative action because he or she is living in an area more likely to prosecute."