A Fathers 4 Justice campaigner who scaled the Houses of Parliament has been acquitted.
Guy Harrison says no one was put at risk by his stunt.
Jurors at Southwark Crown Court found Guy Harrison, 39, had not committed a public nuisance offence during his rooftop protest on 27 September 2005.
Speaking outside the court, the amateur mountaineer from West Sussex, said the "fight will continue" after his acquittal on a public nuisance charge.
Mr Harrison staged the protest to highlight fathers' access rights.
He said: "I'm absolutely delighted at today's outcome which shows yet again the only form of justice in this country is trial by jury."
Jurors heard he had used a Guy Fawkes exhibition to reconnoitre the place, before planning the protest in such a way as to cause the "minimum amount of disruption".
Once on the roof helicopter owner Mr Harrison unfurled a 30ft banner declaring: "Does Blair care? For Fawkes sake change family law."
The prosecution argued that Mr Harrison risked his life, those of others and tied up emergency services as a result of his protest.
But Mr Harrison rejected those claims and said his stunt highlighted security flaws in the House of Parliament.
Fathers4Justice founder Matt O'Connor warned the organisation planned to stage several more events before Christmas.