The Green Party is furious that police-paid spy Rob Gilchrist infiltrated its offices and was used to report on the party's activities.
Green MP Keith Locke said there were rules about how police could act in Parliament's precincts and he would be writing to Prime Minister John Key, Police Minister Judith Collins and Police Commissioner Howard Broad with his concerns.
Mr Locke said that former MP Nandor Tanczos' secretary Rayna Fahey called the party after the story about Mr Gilchrist's activities broke.
Rochelle Rees, the ex-partner of Mr Gilchrist, alleged at the weekend that he had been spying on peaceful protests groups for years.
Ms Rees, an animal rights and Labour Party activist, discovered Mr Gilchrist had been paid by counter-terrorism police to spy on the protest groups when she helped him fix his computer.
She discovered emails between him and police.
Ms Fahey told the Green Party that Mr Gilchrist had befriended her and had been "keen" to visit the office and asked a lot of questions.
This happened in 2005, some time around the election.
"There are clear police protocols in Parliament between the Speaker and the police," Mr Locke said.
"It is very disturbing that police would be conducting surveillance on a political party, including its MPs."
Mr Locke said Mr Gilchrist had also been on a Green Party database getting access to information about policy and activities.
While it was not private it was questionable that police should use it surreptitiously.
Mr Gilchrist had forwarded Green Party information to police about planned protests at Parliament, for example.
Mr Key on Monday ruled out an inquiry into police spying, saying he had been given assurances covert investigations were justified following a meeting between Mr Broad and Ms Collins.
Mr Gilchrist, heavily involved in various campaigns and protests over the last decade, was allegedly paid to pass information on the groups plans and members to the police Special Investigation Group (SIG).
The SIG teams were set up in 2004 to focus on terrorism and threats to national security.
They are reported to have monitored Greenpeace, animal rights and climate change campaigners.
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