The Herald reports:
But the Government and police have strongly rejected this, with Police Minister Anne Tolley calling the claim “unfounded” and a desperate attempt to get a headline in an election year.
More that that it shows Labour doesn't even understand the official crime statistics.
The crime reduction targets have nothing to do with whether people are charged or not. It is basically impossible to reduce the crime rate by not charging people who have been reported as having committed an offence.
To quote Stats NZ:
All reports of incidents, whether from victims, witnesses, third parties, or discovered by police, and whether crime-related or not, will result in the registration of an incident report by police. The incident will be recorded as one or more offences if:
the circumstances as reported amount to a crime defined by law, and
there is no credible evidence to the contrary
Whether or not someone is charged has no impact on whether the report is recorded as a crime.
The violent crime stats tend to be the most reliable, because they are based on complaints being laid. Other categories of crimes can rise or fall depending on how much energy the Police put into them, especially drug crimes. Drug crimes do not normally involve a complainant, so the level of recorded drug crime will depend on how much effort the Police put into the area. But violent crime is almost entirely based on complaints from victims or witnesses, and a decision to not charge an offender will not impact the crime stats. It will impact the stats on charges and convictions, but they are different stats to the crime stats.
So the short version of this is that Labour are talking through a hole in their head. They just don't understand that even if their allegation is true (which I would not assume to be the case), it doesn't impact the crime stats.