A radio satellite station capable of being used for ballistic nuclear missile targeting was secretly built by the French on the Chatham Islands, newly-discovered and declassified documents reveal.
When defence officials discovered the existence of the newly-built antenna in 1989, it caused alarm and saw the issue rapidly escalated to the Top Secret committee charged with matters of national security.
The year which followed saw dismay over how such technology could be secretly installed in New Zealand, questions over behaviour by newly-corporate Telecom and continuing anger over France's nuclear testing and the deadly attack on the Rainbow Warrior.
A Herald investigation into the Project Doris incident has revealed a fascinating slice of our secret history and the tensions of the time.
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It pitted the opposing demands of a fractured Labour Party against each other - those who wanted to live the dream of a nuclear-free world and those who worried about how to pay for our way in it.
And it came by way of the Government's policy to turn public infrastructure into "state-owned enterprises" and demand they run like businesses.
Telecom did just that - and did a deal with French government scientists to build an antenna on the remote Chatham Islands which could be used to improve targeting of its nuclear ballistic missiles.
Thirty years on, the French science project which caused such grave concerns is enjoying a second lease on life on a remote section of the Chathams. The deeply-felt anger and frustration felt in the dying days of David Lange's transformative Government wasn't present a decade on, when Project Doris made a return.
April 29, 1989, was a different matter. That was the date on which Lange chaired a meeting of the secret Domestic and External Security Committee.
Minutes held in Archives NZ instructed: "Steps to be taken immediately to have dismantled France's Project Doris radio beacon which has been installed on the Chatham Islands."
The minutes continued with an instruction the dismantling happen in as low-key a manner as possible.
Politicians were eager to avoid damaging relations with France as there were European Commission "access decisions on butter and sheepmeat in the next 6-8 weeks".
And, of course, it was important to make sure state-owned enterprises didn't cause any more diplomatic incidents.
By the October 1989 DESC meeting, Lange was gone. Geoffrey Palmer - now knighted - was Prime Minister although wasn't chairing the Top Secret meeting.
That task fell to Russell Marshall, Minister of Foreign Affairs and, fittingly, disarmament and arms control.
The meeting was told there were scientific benefits to Project Doris but it had to be "balanced against the fact New Zealand would be hosting a facility with some potential in future to enhance French nuclear weapons targeting".
It went on to say "the manner in which the French had the beacon installed without proper consultation in advance with the New Zealand Government was unacceptable".
Yes, said the minutes, the French had been helpful advancing New Zealand's trade into Europe but they must be told furtive installation of the antenna was "unacceptable".
Rather than instantly dismantling, though, the French Government was told to make a "formal request" and "full justification" for the project, and to do so before the launch of the satellite the following year which would make the beacon active.
It didn't matter. A Cabinet paper from February 1990 - just a few months later - showed there was no interest in concessions to the French. The "irregular arrangements" and failure to convince the Government the military use was negligible meant Project Doris was over.
By then, some of the details had been made public forcing Palmer and Fran Wilde, who took over from Marshall as Minister for Disarmament, to calm the public by stating it had never been operational.
Wilde's detailed memo for Cabinet is the best current record of New Zealand's first brush with Project Doris, which was an acronym for Doppler Orbitography and Radio Positioning Integrated by Satellite.
The system was devised in 1986 by France's National Geographical Institute and was intended to have radio antenna placed across the world to beam signals to satellites. The passage to and fro would allow scientists to accurately measure land masses, and later, sea levels.
The French scientists wrote to New Zealand's Department of Scientific and Industrial Research asking if it could set up a beacon on the Chatham Islands. The DSIR told the Post Office because it already had equipment there, and the Post Office internally approved the idea.
The Post Office was broken into three parts in 1987, of which one was Telecom.
It had inherited New Zealand responsibility for Project Doris, and perhaps because it didn't come with a commercial return, it was a French engineer who headed out to the Chatham Islands in 1988 to install the beacon and equipment.
The beacon was one of 50 around the world, Wilde told Cabinet. The interchange of signals between all beacons and satellites would allow a new level of precise mapping.
It wasn't active - when turned on in early 1988 the signal caused interference with the Post Office's meteorological equipment so it was turned off while waiting for proper radio licence approval.
It was about this time the Ministry Of Foreign Affairs and the Ministry of Defence learned of its existence. It sparked a frenzy of information gathering, first from allies and then directly from the French Government.
Demands for technical details were sent to Paris, and responses back to Wellington which led to the DESC meeting at which Lange and others decided it should be dismantled.
It wasn't, not for a year and not until DSIR had made a plea for it to stay because of its civilian scientific value.
Wilde's memo records the downside: "Accurate geodetic information and knowledge of the gravitational and other forces acting on space vehicles are important to determine the trajectories of ballistic missiles.
"The French independent nuclear deterrent includes such. Missiles."
Wilde points out any contribution from a New Zealand-based beacon would be small - the effect was greatest along the paths missiles were fired and those routes didn't include New Zealand.
Key allies Australia and the United States were also unhappy about the project. Australia had demanded France remove two beacons which were installed in 1987 with its government being told.
The Australians objected because the data could be used for spy satellite mapping, and could be shared with the USSR. The beacons were removed without the public knowing, or being told.
New Zealand's High Commission in Canberra was also told the US had blocked beacons being placed on an atoll and on the US mainland.
Wilde said there was "an added complication" - getting butter and sheepmeat into Europe.
France held the presidency of the European Community during the second half of 1989. It was, she said, "advisable not to antagonise them at such a crucial stage by insisting on the removal of the Doris beacon".
Having secured New Zealand's access to 1992, with French help, it was now time to make a decision.
"Having reviewed all the information on the subject I feel bound to return to my initial recommendation, which was to the effect that the beacon would be unlikely to benefit
New Zealand in any substantial way and that it should be dismantled."
Wilde recalls the drama of Project Doris, and the emotional weight of the Rainbow Warrior bombing along with the intense negotiations to break into the European market.
"And France was the key. The Government was really treading a knife edge to call out behaviour we didn't agree with while looking to the economic prosperity of New Zealand. It was very, very difficult."
The potential for Project Doris to be used for nuclear weapons targeting "outweighed everything else for me", she said. "I think we did the right thing."
Dr Clive Matthewson, who served as DSIR and State Services minister, recalled the balancing act between trade and attitudes to nuclear weapons. As part of the 1984 intake, he was "very strongly anti-nuclear" and still angry with the French.
As was the Labour caucus, he said, with MPs at the time having influence over Cabinet.
"The mood of it would have been to tell the French to go away."
Records on the Project Doris website shows a beacon was eventually installed and switched on in 1999. The rest of the world has also moved on - Australia has Project Doris beacons, and there are multiple beacons across the United States.
The project is referenced in a multitude of academic works. France has yet to fire a ballistic nuclear missile in anger.
The same French science body retains control - the National Geographical Institute. It includes international partners such as Nasa, while in New Zealand, its management is handled by Land Information New Zealand, which in turn subcontracts it to Geological and Nuclear Science, a Crown research institute.
Dr Frank Lemoine, chairman of the International Doris Service, confirmed the radio station was removed in 1990 at the request of the New Zealand Government.
Six years later, the Doris project began fresh discussions with the GNS predecessor, the Institute of Geological and Nuclear Sciences.
It led to a formal application to the Ministry of Foreign Affairs and Trade in 1997. Then, under a new government, Project Doris was told New Zealand "would welcome and support an installation by the French".
The government approval was one thing - it wasn't until December 1998 the Chatham Islands Council added its support and the new radio beacon was installed and operating by the following February.
Lemoine said since then, the beacon on the Chatham Islands had fed into a network of 60 other beacons which had helped measure the shape, rotation and gravity field of earth.
The Doris system allowed measurements on earth down to 1cm accuracy, helping measure our planet's oceans but also to contribute to weather forecasting, specifically on cyclone intensity.
Lemoine said it had become a true international, scientific endeavour.
Retired GNS engineer Colin Dyer has no recollection of politics following Project Doris through its life. He became involved in 2001, at one stage visited the Chathams to help replace the antenna and retired in 2017.
"That was all history by the time I came along."
It has moved a couple of times during its life on the Chatham Islands. Mayor Alfred Preece currently hosts the antenna after his neighbour decided he wanted it gone.
"It's gone over the fence to my place."
The systems are automated. The beacon does what it is meant to do, and if it stops, then someone - as Dyer did once - comes over from the mainland to fix it.
Preece recalls the fuss. "My memory of it was it was a bit of a storm in a teacup. Any excuse to give the old frogs a belting."
Thanks to Dr Matthewson for allowing the declassification of the Project Doris Cabinet memorandum from among ministerial papers held at Archives NZ.