Is the government playing 'fast and loose' with gang numbers?

The government has been accused of playing "fast and loose" with statistics in order to claim its gang crackdown has slowed ballooning membership.

Earlier this year, Prime Minister Christopher Luxon and Police Minister Mark Mitchell acknowledged the police's national gang list had been "sanitised" and indicated they would not use the corresponding drop in numbers to claim success.

And yet in an interview with RNZ published Monday, Luxon did just that, claiming gang membership had grown just one percent under his watch, compared to the explosion under Labour.

"We've stabilised gang growth," Luxon said.

Mitchell also pointed to the gang list last week to claim membership growth had "slowed tenfold".

As of 10 October, the national gang list had 9460 names, up one percent from 9366 at the end of December.

Mitchell compared that to a similar period the year before under Labour, where numbers climbed from 8443 to 9270, up 9.8 percent.

But the comparison did not take into account an "exceptional" police audit of the list this year, which saw 791 names removed between February and July.

University of Canterbury sociologist and gang expert Jarrod Gilbert told RNZ the government was wrong to use the figures to claim it had made a dent in gang growth.

"You just can't go into the database, remove all of the people that should never have been on there, and then holler 'success'.

"It's so easy just to run fast and loose with this gang list... you're basically comparing an apple with an orange."

Labour police spokesperson Ginny Andersen also voiced concern, telling RNZ the government needed to come clean about its use of the statistics.

"The government has publicly stated they have sanitised the gang list. That is incredibly dubious to then champion it as a stabilisation of those numbers."

But in a statement to RNZ, Mitchell doubled down on his claim: "The numbers are the numbers."

Mitchell also took a dig at Andersen, saying she needed to stay away from statistics. Anderson copped criticism in August for misusing data to claim police foot patrols were down, when they were up.

Mitchell pointed out the police carried out a similar audit of the gang list in late 2021 and said it was the police's prerogative to regularly conduct quality assurance.

"The national gang list is police's operational intelligence, it is the most reliable picture that we have of gang membership in this country."

But Gilbert said the list was simply not an accurate gauge for assessing gang numbers.

"It's great for rule of thumb. But to use these precise percentages is crazy... it was never, ever meant to be a census of gang numbers."

Gilbert said as well as the issues with occasional "sanitisation", the list was prone to grow faster than the reality.

"It's much, much easier to identify gang members who have entered than it is to identify people who have left," he said.

"You had people on that gang list from gangs that no longer existed."

Similarly, in 2021, former police commissioner Andrew Coster told MPs the gang list was an intelligence tool, not a statistical one, and therefore not an accurate reflection of active gang membership.

In his earlier interview with RNZ, Luxon dismissed suggestions the police purge undermined his claim of progress.

"You'd be insane to argue, mate, that that was a great record from the Labour government," Luxon said.

"But more importantly, what we're interested in is actually seeing a reduction in crime."

The government last week released statistics showing victimisations to the end of September had dropped three percent compared to the same period last year.

In September, Luxon also snapped at a reporter who suggested the list's sanitisation was "convenient" for the government.

"It's not about the frickin' targets," Luxon said. "It's about outcomes."

Both Luxon and Mitchell were also asked for a commitment they would not celebrate a drop in gang numbers due to the audit.

"You haven't heard us do that," Mitchell said.

"We're not celebrating anything," Luxon added.

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