The cab rank rule expresses a beautiful idea: that access to the law – society’s great leveller – is for everyone, whoever they are and whatever they are said to have done. The rule remembers that for a lawyer to say “I will not act” appropriates a role the system gives to judges or juries. And it recognises that if lawyers are tainted by association, the criminal justice system is jeopardised. It risks, or even ensures, miscarriages of justice. What it says is that we barristers act for whoever seeks our services – in the same way taxi drivers in a rank take whoever is next in the queue – whether we like the look of them or not. And it is not just an idea, it is also a professional conduct obligation. If we breach it, decide we will not act for someone because we don’t like who they are or what they do, we commit professional misconduct – and face disciplinary sanction. We could be fined, or suspended – even struck off. It’s only right, then, that I answer the questions raised by my support of a new declaration, signed by me and more than 100 other lawyers, in solidarity with all those on the frontline of the climate and ecological crises. Some of those questions have been raised on the front page of Friday’s Daily Mail under the headline, “Fury at woke barristers refusing to prosecute eco warriors”. It accuses us of “virtue signalling” and “undermining the legal system” by declaring that we will not prosecute climate activists, regardless of how they appear in the “cab rank”. The rule has always been relatively easy to dodge – barristers can and do hike their fees or make themselves unavailable. It doesn’t apply to the larger branch of the profession: solicitors. It is often used, by those whose professional lives demonstrate no interest in access to justice, to shield barristers from criticism for self-interested decisions to act for wealthy rogues. In the real world it is money, not character, that divides those who do and don’t get to use the law. And the rule does little to help the millions who are denied the power of the law because they are poor. And yet, still, it represents a beautiful idea. There are barristers I can and do ask to act for low rates, even for nothing, for those who need the law. And they say yes because the cab rank rule, for them, is an article of faith. I admire and respect them, and the principles they cleave to through their conduct. So I want to explain to them, and to the public, why I have signed a declaration that I will not act for those developing new fossil fuel projects or against those who protest to try to stop them. The cab rank rule is bound up, inseparably, with the idea that the law is right and its ends are worth upholding. But the law is not always right. Sometimes the law does not reflect the democratic preferences of the people. Sometimes the law is ugly and sometimes it is wrong. Sometimes it evidences the pernicious influence of money on politics. Sometimes the law is the victory dance of power. Like big tobacco, the fossil fuel industry has known for decades what its activities mean. They mean the loss of human life and property, which the civil law should prevent but does not. The scientific evidence is that global heating, the natural and inevitable consequence of its actions, will cause the deaths of huge numbers of people. The criminal law should punish this but it does not. Nor does the law recognise a crime of ecocide to deter the destruction of the planet. The law works for the fossil fuel industry – but it does not work for us. Sometimes the law is wrong. What it stands for is the opposite of justice. Today’s history books speak with horror about what the law of yesterday did, of how it permitted racism, rape and murder. And tomorrow’s history books will say the same about the law as it stands today, of how it enabled the destruction of our planet and the displacement of billions of people. This is why, with respect, it is wrong for the former lord chancellor Robert Buckland to suggest hypocrisy because I would act for those accused of crimes of violence but not for the fossil fuel industry. The difference is that I support the law that imprisons those convicted of violence but I cannot support laws that permit new fossil fuel projects. We should not be forced to work for the law’s wrongful ends by helping deliver new fossil fuel projects. We should not be forced to prosecute our brave friends whose conduct, protesting against the destruction of the planet, the law wrongly criminalises. That is a beautiful idea, too. Jolyon Maugham KC is the director of the Good Law Project and author of Bringing Down Goliath: How Good Law Can Topple the Powerful