Labour's police spokeswoman Jacinda Ardern has been barred from meeting with Tasman district's police commander.
Police Minister Anne Tolley says police are too busy.
"I agree with the Police Commissioner that during this busy time of the year it is better for police to be out preventing crime rather than acting as tour guides for politicians," the minister said.
Ms Ardern was in Nelson this week visiting organisations. However, her request to meet with Tasman district commander Superintendent Richard Chambers was declined.
She said she was baffled by the rejection.
In a letter to Ms Ardern on November 22, Mrs Tolley explained the summer period was an extremely busy time of the year for the police as they prepared for potential operations over the Christmas period.
She had recently been advised by the commissioner that it was not a good use of police time to facilitate visits by MPs during the period for that reason, she said.
However, in the New Year her office would provide a list of potential dates, it reads.
Ms Ardern, who took over as Labour's police spokeswoman nine weeks ago, said it was important for her to build a relationship with police.
As a daughter of a long serving policeman of 40 years, it would be offensive to presume the police did not have any time to discuss issues that were pertinent to the successful running of a community, she said.
"I think most would think it was an absurd suggestion to be spoken for," she said. "I'm completely baffled by it."
It was important not to politicise the police and their work and the minister's rejection was doing just that, she said.
"Of course we know the police are very busy, and we go out of our way to try and accommodate them, and the visa versa.
"We use our good judgment. We are not going to ask to see the police in Thames or the Coromandel over December or January, for instance," she said. The minister was putting the police in a compromising position, she said.
Nelson-based Labour list MP Maryan Street said the situation seemed odd seeing as it was not election year.
It was understandable that ministers would refuse to grant a request to see public servants to prevent them becoming the meat in the political sandwich during election year but not now, she said.
If other party spokespeople could not get around their departments and get a feel for local issues, they would be put in a position where they could not do their jobs properly, she said.
Mr Chambers, was not to blame, she said. He was always helpful and readily available.
Two Labour MPs went to the police station for an unrelated appointment and were shown around the station anyway, she said.
And even despite the rejection on the grounds of summer facilitating, Mr Chambers would not have been able to attend because he was not in Nelson at the time, she said.
She suspected the minister did not want the opposition talking to public servants as they were subject to a great deal of pressure thanks to the current government, she said.
"It is becoming clear that the police are feeling the pinch," she said. There had been many cutbacks over the last two years, she said.
Mrs Tolley said such an assumption was nonsense. There were protocols and there always have been for MPs to talk to a district commander.
A police spokesperson, on behalf of the commissioner,said the lead-up to Christmas was a busy time.
The commissioner would like police staff to be fully focused on the job of preventing crime and crashes plus keeping communities safe at this time of year, he said.
Police would be happy to facilitate visits by MPs in the New Year when the holiday period was over.
"Of course any urgent requests from MPs will be considered on a case by case basis," he said.
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