It is a complicated defence, the defence of necessity. Last week, 20 people admitted their plan to shut down Ratcliffe-on-Soar coal-power station, but justified their actions as being to prevent death and serious injury from the carbon emissions. A jury heard compelling evidence on the horror of climate change, but still returned a guilty verdict. We'll never know what those 12 people discussed, but that governments are failing us all is clearer than ever.
Yes, they were acting – or planning to act – through an unconventional process. Had the plan gone ahead, arrests would have been inevitable. But, given time to present their evidence, research and sophisticated safety measures, the defendants adeptly explained why their actions were reasonable.
Not only would they have prevented the release of 150,000 tonnes of carbon dioxide (more than they could ever have saved in their lifetimes) in a week-long shutdown, but these people could have saved human lives in the future. Any doubts about the urgency of climate change or its impact on human health and social stability were addressed by a prolific selection of expert witnesses, including the Nasa climatologist James Hansen and the epidemiologist Anthony McMichael.
Which leaves as the only issue whether this was a reasonable response to the urgent climate crisis. And that centres on one question: is there any hope for conventional channels of political change, both nationally and internationally?
During the case, both I and Alan Simpson, a former MP, gave evidence to explain the "democratic deficit" – the fact that governments are not responding with anywhere near the urgency that climate change demands. The UK has passed legislation to cut emissions by 80 per cent by 2050, but as there is no actual plan to achieve even this inadequate target, we are continuing to pollute. Internationally, we have just seen the Cancún summit fail to achieve any legally binding agreement, and the most immediate ramifications continue to hit vulnerable people who have done nothing to cause this crisis.
Perhaps the jury was persuaded by the prosecution arguments that we can save the climate through small individual actions like compost loos and second-hand clothes. These are important, but history shows that there have always been people working against the grain to create essential change.
The civil rights movement and the suffragettes are examples of normal people making a difference by stepping outside their comfort zones. An example closer to home is the "Kingsnorth Six" – Greenpeace activists who were charged with criminal damage after scaling Kingsnorth coal-fired power station, yet were eventually acquitted in a similar case to this one.
There are some politicians in parliament willing to make climate change an overriding priority of the government and it's crucial to have them there. But by and large, the political process continues to support business as usual – and the tiny reforms discussed in Cancún fail to address the root causes of climate change. Any improvements we gain from such a deal will make little, if any, long-term difference to the lives lost and species destroyed.
The Ratcliffe activists are part of a wider grass-roots movement working for climate justice. The People's Summit in Cochabamba, Bolivia, in April this year, showed that people are coming together in all kinds of ways, to deliberated as well as take peaceful direct action, to seek serious alternatives, while governments continue with their frustrating inaction.
As the defendants said after court, "Taking action on climate change is not an act of moral righteousness, but of self-defence." While so many politicians are failing in their duty to act on behalf of the people, and while the legal system continues to protect big polluters, we all should learn something from those willing to take action on climate change.
Caroline Lucas is leader of the Green Party and MP for Brighton Pavilion.