updated 06/14/2012 AT 8:00 AM ET
•originally published 06/14/2012 AT 8:30 AM ET
Lucy Lawless pleaded guilty Thursday to trespassing, and had a more serious charge of burglary dropped, after she and seven other Greenpeace New Zealand activists boarded an oil-drilling ship in February to keep it from leaving port.
The Spartacus: Vengeance actress, 44, could face three years in prison at her sentencing in September, but told reporters in Auckland that she doesn’t expect jail time, as she is a first-time offender and the protest was peaceful.
“I had to do what I had to do,” she said, reports the New Zealand Herald. “We want to tell [deep-sea oil drillers] absolutely under no circumstances is this a good idea. They are robbing our children of their birthright to a clean and healthy planet, and they know it.”
The eight protesters entered a restricted area at Port Taranaki on Feb. 24 and boarded the Shell-owned Noble Explorer ship to prevent it from sailing to Alaska to drill exploratory oil wells.
The activists sat atop the ship’s 175-foot drilling tower for 77 hours. “I think we’ve helped kick off a great movement,” Lawless said Thursday, pointing to the extensive media coverage of the stunt.