A protest which halted a mining giant's oil exploration on New Zealand's high seas and prompted a controversial law change cost taxpayers nearly $1.7 million, documents show.
The Defence Force and New Zealand police were sent to the Raukumara Basin in April 2011 when a protest flotilla led by an East Cape iwi interfered with Brazilian company Petrobras' seismic surveys.
Tauranga fisherman Elvis Teddy was arrested by police, but the charges were dropped because the incident took place outside New Zealand's 12-mile territorial limit.
The High Court overturned this decision, and Energy Minister Simon Bridges introduced an amendment to clarify the law and create new offences covering interference with mining companies on the high seas.
Ministry of Business, Innovation and Employment documents show the Defence Force deployment was estimated to cost $1.08 million, based on the deployment of two patrol vessels and personnel for 40 days.
The direct cost to police was estimated at $585,000, which included sending 12 full-time staff to the region for 42 days.
Protesters' ships came within 20m of the Petrobras-commissioned Orient Explorer, and some activists swam 200m in front of the vessel, forcing it to veer off course. Officials said seismic vessels could not immediately stop because they were pulling long seismic "streamers" or lines, and if they veered too far from their course it could take four hours to loop back to their original path.
As a result of the protests, Petrobras had to halt its surveys for nearly two days. It has since handed back its exploration licences for New Zealand waters.
Mr Bridges' law change, which was passed last week, means protesters who intentionally damage or interfere with mining sites or vessels which are outside New Zealand's 12-mile limit risk up to a year in prison, or fines of up to $50,000 for a person or $100,000 for an organisation.
The law also gives police and Defence Force personnel power to board protesters' ships and arrest and detain them.