Police seized the text messages of a photo-journalist involved in the "teapot tape" saga, including exchanges with his family, his lawyer and Herald on Sunday journalists.
Auckland University associate law professor Bill Hodge describes the police actions as "mind-boggling".
The Herald on Sunday has obtained the dossier of about 323 text messages sent and received by cameraman Bradley Ambrose, in the days before and after the notorious cup of tea between Prime Minister John Key and Act candidate John Banks during the 2011 election campaign.
Texts between Ambrose and his lawyer Ron Mansfield were among those seized by police, in what Mansfield says was a breach of lawyer-client privilege.
The revelation comes hard on the heels of the discovery that logs of Fairfax political journalist Andrea Vance's phone calls and emails were supplied by the Parliamentary Service to the Prime Minister's inquiry into GCSB leaks, and the allegation that the NZ Defence Force asked its US counterparts to track the communications and movements of war correspondent Jon Stephenson.
This weekend, the new case of police secretly reading a journalist's communications has heightened concern about authorities cracking down on media that publish information embarrassing to the Government.
John Key had called in police to investigate whether Ambrose had deliberately recorded the eight-minute conversation in front of a media pack in a Newmarket cafe, after Ambrose gave the recording to the Herald on Sunday.
The logs of Ambrose's text messages and phone calls were disclosed by Vodafone NZ after police served a search warrant on the company on January 24 last year, two and a half months after the incident. The text messages appear to confirm that the recording was inadvertent, not a deliberate News of the World-style conspiracy as Key had claimed.
Ambrose had always said he left his microphone on the cafe table inadvertently, and the police investigation discovered no evidence to the contrary. Ambrose wrote a letter of regret to the Prime Minister about the accidental recording, and no charges were ever laid.
Now, police have been forced, under the Official Information Act, to supply their investigation file - which stretched to several hundred pages long.
It contains text message exchanges between Ambrose, Herald on Sunday senior journalists, and 3News boss Mark Jennings, referring to legal discussions and the possibility Ambrose might take defamation action. Ambrose did not want to comment yesterday.
But Auckland University associate professor Bill Hodge said it was "mind-boggling" police would intercept text messaging over such a minor charge, especially when the Evidence Act 2006 provided clear protections for journalists to guarantee the freedom of the media. "Why in hell would they have those, for what investigatory purpose?" he asked.
"The police do have the capacity to get a warrant. I wouldn't have thought this was a case that required text messages."
The Evidence Act says journalists cannot be compelled, in any criminal or civil proceeding, to answer questions or produce documents that might reveal the identity of a source. Only a High Court judge may order a journalist to produce such documents, and only if there is an overwhelming public interest.
But in this case, police obtained Ambrose's communications from Vodafone without his knowledge.
Hodge said the seizure was "greatly concerning". "Any person with a bit of legal knowledge should be having alarmbells go off."
He said it bore similarities to the case where Andrea Vance's calls and emails were accessed without her knowledge - in both cases, inquiries initiated by the Prime Minister. "If you're a sworn member of the police you're probably going to put a little more resource into it if the request has come from the Prime Minister," Hodge said, "although in theory under the law it's the same as everybody else".
Ron Mansfield called for a review of the rules enabling police to obtain text messages and phone calls.
"I think the police access to communications is too freely given and not sufficiently monitored," he said. "It's time we reviewed this important issue of privacy as a community. We need to determine what is appropriate and how it is protected.
"I would steadfastly fight to maintain my clients' ability to communicate with me without fear of those communications being intercepted or obtained by the police. Clients have to be able to communicate freely and frankly."
Police spokesman Ross Henderson said police had believed that there had been intentional interception and disclosure of private communications. Obtaining the relevant records was therefore important in providing information relevant to the inquiry, he said.
"When seeking a warrant in these circumstances, police are obviously unaware of the exact nature and content of any information that might be provided. Any information that is subsequently received and not considered relevant to our inquiries is disregarded."
The tape dominated coverage in the final weeks of the election campaign and gave plenty of airtime to New Zealand First leader Winston Peters, who publicly hinted at the contents of the conversation.
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