In September, a British jury found 28 members of the environmental group Greenpeace not guilty of criminal damage to a genetically modified maize crop. The activists did not deny that they trashed the 1999 crop, but claimed "lawful excuse" because they believed they were preventing genetic pollution.

The ruling is seen as a setback for this biotechnology. Faced with an "open season" next summer, farmers may be less inclined to host field trials. Some would even suggest every crop sprayer and fertilizer distributor in Britain is now a legitimate target for direct action by anybody who "genuinely" believes in the environmental benefits for organic food production.

But the acquittal of the Greenpeace 28 may yet backfire. Most farmers support genetic engineering technology. They are waiting quietly for the green light of environmental approval. As the eco-activists are now seen as a threat, rather than just a nuisance, many farmers now feel the need to get off the sidelines.

As well, halting the trials gains nothing in itself - the activists need to convince government to pass legislation banning the growing of genetically modified crops.

At the moment, it's perfectly legal to grow, harvest and sell genetically modified crops, but the industry - and more moderate environmentalist groups - agreed to a three-year moratorium to allow environmental tests. The best hopes for those opposing genetically modified crops is unfavorable reports from these field trials.

The next best hope is to persuade the British government to abandon its science-based policy in favour of a popular blanket ban on the technology. The Labour government is approaching an election, its popularity is on the decline and it was badly hurt by being on the wrong side of public opinion on the recent fuel taxation issue.

But this biotechnology issue doesn't excite the same interest. If the activists use the jury decision to go on a crop-wreaking spree, they are likely to antagonize the public in short order.

The jury decision may just provide enough rope for the activists to hang themselves.

For CBC commentary, I'm David Walker, an agricultural economist, at Lodge Farm Postwick in Broadland Norfolk, England.

David Walker was senior economist for Home-Grown Cereals Authority in London and previously was executive director of the Alberta Grain Commission. His opinions on British and European agricultural issues can be found at www.openi.co.uk/