Lord Melchett, the executive director of Greenpeace, helped to destroy a field of genetically modified maize to prevent pollen from the crop polluting the countryside, a jury was told yesterday.
The former Labour government minister told Norwich Crown Court that he and 27 other Greenpeace supporters carried out the attack on the field at Lyng, Norfolk, in July last year with a "great deal of seriousness".
Lord Melchett, 52, of Hunstanton, Norfolk, and his 27 co-defendants, who all deny theft and criminal damage, argue that they had a lawful excuse to destroy the maize because they held a genuine belief that neighbouring organic crops were in immediate need of protection.
"It was a genuine attempt as far as I was concerned to stop and remove this genetic pollution," said Lord Melchett, a minister in the departments of environment, industry and in the Northern Ireland office during the 1970s. "I went to the field with the intention of trying to remove any crop and trying to return it [to the owner]."
He added: "It had been reported in Farmers' Weekly that the crop was about to pollinate within about seven to ten days. It is at the point of pollenisation that the genetic pollution of a crop of this sort becomes uncontrollable."
He said the people taking part in the protest, who wore white boiler suits but made no attempt to hide their identities, had been told to act on their consciences and not to be violent. The demonstration was videotaped by Greenpeace and witnessed by an invited journalist.
Lord Melchett added: "I think GM is one of the most serious issues Greenpeace has ever tried to tackle. We don't have a religious objection to it. We would not object to scientists doing experiments in labs which are contained and controlled. What worries me is when you use this for crops you are putting it out into the environment on which all human and animal life de-pends and we know very little about it."
Owen Davies QC, for the defence, said the 28 defendants included a Baptist minister, Malcolm Carroll. Mr Daviescompared the way the demonstrators acted to a firefighter breaking down a wall to reach an injured person. The QC stressed the defendants had only to establish that they held a genuine belief - not that their belief was right.
John Farmer, for the prosecution, said the GM maize was being grown on 2.4 hectares of land as part of an experiment being conducted by theGerman-based agrochemical company Aventis, which was formerly known as AgrEvo.
The case was adjourned until today.