New figures show the prosecutions against three protestors who vandalised the Waihopai spy base cost the Crown at least $146,000.
The criminal prosecution cost $53,000 before the Crown abandoned it in 2010 and instead launched a civil lawsuit.
Figures released under the Official Information Act show that the civil action cost at least $93,000.
Most of it was paid by the Government Communications Security Bureau which runs Waihopai near Blenheim.
Last week the Crown dropped the civil lawsuit, in which it was seeking $1.2 million in damages, saying it had proved the point that activists can't break the law just because they feel strongly about something.
