Nearly 170 sworn police officers left their jobs between March and July this year, the equivalent of all police staff deployed to managed and isolation quarantine (MIQ) facilities.
The association says the Government has dropped the ball on funding new recruits and those on the frontline are now paying the price.
"It's as simple as this; police will not be able to attend as many calls for service if those numbers don't get back up to where they should be," president Chris Cahill said.
Attrition rates had dipped during the Covid-19 pandemic as seasoned police officers held off retiring, he said.
However, the number of officers leaving the job has spiked to 168 in the four months to July 2021. That means progress on reaching the target of 1800 extra officers has slipped from 1339 in March to 1171 this month.
Cahill said some of these exits are retirements but morale has taken a hit in recent months due to increasing workloads, risk and stalled pay negotiations.
"Workloads are definitely increasing, whether it's that 44 percent increase in family harm events in the last three years or 68,000 mental health crisis interventions in the last 12 months. That hurts.
"You throw in the risk - more assaults are happening and the threat of firearms - and then you get things like a pay freeze announced; the government's not offering any meaningful pay rise to police officers. It all adds up to make them feel pretty undervalued."
Cahill said the Police Association had forewarned a spike in attrition and asked the Government to release money allocated for new recruits early, to combat it.
"That's why we always said you need to keep the recruitment going and the funding flowing through even if the attritions drop because it will catch up.
"Now it has and unfortunately we're seeing those frontline numbers drop because they've not kept up that recruitment."
The Government has failed to deliver its promised 1800 new police officers in three years to bolster the workforce.
Instead, it has scaled this back to two goals; 1800 new recruits, which it has met, and a net increase of 1800, which might take longer than three years.
Cahill said there are up to 2000 people waiting to get into the Police College who can't because the Government won't release funding allocated for the next financial year.
He can't understand why the money can't be put to use now, given the net increase targets and rising attrition rates.
"That's an issue we really can't understand. These are jobs they can create by releasing that money early. They're good people that want to join the police now; they're available to join.
"It just seems to us that it doesn't make sense not to bring the funding forward. And, as I say, we're paying the price for that now with actually seeing numbers take a significant dip."
The National Party's police spokesperson, Simeon Brown, said it's the Government's job to ensure frontline officers feel safe and supported.
"Our frontline officers do accept some risk when they go and take that job, but they are the human face of the law. They're representing the law and they're the ones who have the job of enforcing it.
"We should absolutely be showing them the respect they deserve. The government's job is to make sure they feel respected, they feel valued and they feel safe."
The ACT Party's police spokesperson, Chris Baillie, a police officer himself for 14 years in Nelson, Wellington and Auckland, said he wasn't surprised attrition rates have spiked.
"[It's] just the lack of support; they're facing more violence, they're facing more work and the numbers are going down. They're facing wage freezes.
"Just the overall support. I was talking to a couple of cops the other day and they had no idea who their current police minister was."
RNZ approached Police Minister Poto Williams for an interview for this story but was repeatedly told she wasn't available.
Cahill said the Government may soon face some tough decisions that may impact the country's first defence to Covid-19 if it doesn't act now.
"I know police are concerned that, with these numbers dropping, they don't have the ability to put these police staff into those managed isolation facilities and that's something the government will have to consider.
"If the numbers are too low to actually put frontline officers out on the streets, then they'll have to remove them from managed isolation facilities."
