In the Sharma case, Australia’s federal court must not avert its eyes from the climate crisis

What is the role of Australia’s judges in confronting the climate crisis? That weighty question came before the federal court this week. The outcome in Environment Minister v Sharma will have far-reaching implications for the course of climate action in Australia.

Such is the nature of our pandemic experience that the most consequential climate case yet was argued not in a grand courtroom but via Microsoft Teams. As the solicitor general, Dr Stephen Donaghue QC, for the minister and Noel Hutley SC for the respondents – a group of Australian teenagers – went head-to-head, the hearing was smattered with the usual videoconferencing hiccups. “You’re on mute, your honour,” was often repeated. At one point the chief justice, James Allsop, quipped that his barking dog had been “referred to as a god in the transcript”.

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These moments of levity barely punctuated the solemness of the occasion. It was evident in the demeanour of the three judges, and their frequent questioning of the interlocutors before them, that the bench understood the acute significance of their task. In the years to come, history will judge these distinguished jurists on their ultimate decision.

To understand the significance of the Sharma case, it helps to begin at a cafe in Paisley, a town in Scotland, almost a century ago. May Donoghue was pouring from a bottle of ginger beer when a decomposed snail is alleged to have fallen out. What came next is embedded in the minds of all first-year law students. Donoghue fell ill – she sued, won, and set the course for the modern law of negligence. Lord James Atkin, a Queenslander by birth, declared: “The rule that you are to love your neighbour becomes in law you must not injure your neighbour.”

Negligence, a subset of the law of tort, thus came to govern personal injury. Those injured in a car crash, in the workplace or elsewhere have legal remedies on the basis of the snail in the bottle. Last year, a cohort of Australian teenagers and their litigation guardian, a nun, sought to extend this principle to climate change. With the environment minister, Sussan Ley, on the cusp of approving a major expansion of Whitehaven’s Vickery coalmine near Gunnedah, the teenagers sued to stop her.

In a world-first judgment, Justice Mordecai Bromberg of the federal court partially upheld their claim. The minister, Bromberg wrote, owed the kids a duty of care to prevent climate harm – and consider that duty in approving the mine expansion. Climate change, he added, would be “the greatest intergenerational injustice ever inflicted by one generation of humans upon the next”.

This week, before the full federal court, the parties argued about whether his honour was right. Depending on who you believe, the Sharma case is either a radical over-reach by the judiciary, contrary to fundamental separation of power principles, or an entirely ordinary evolution of negligence adapting to these changing times.

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If the teenagers prevail, ongoing federal government support for fossil fuel extraction and combustion will become untenable. Major private emitters, such as AGL – Australia’s largest corporate emitter – could also face lawsuits. It is no exaggeration to say that Sharma might change the course of Australia’s climate inaction. On the other hand, a win for the minister would pose a major obstacle to transformative climate litigation in Australia. It could even see the courts effectively vacate the climate field.

On Monday, the solicitor general argued that the policy-laden world of climate action is not suitable for the judiciary. He borrowed on arguments frequently deployed in the United States, to the effect that judges should not enter this political thicket. Donaghue submitted that, if Australia doesn’t dig up the coal, someone else would. And in any event, he continued, the Paris agreement had all this covered. The mine’s coal will be combusted overseas – in other words, it is not Australia’s responsibility.

The court should reject these arguments. That climate change is a complex problem, and in Australia has been deeply politicised, does not render it unfit for judicial engagement. As the high court said in the Brodie case, no lesser principle than the rule of law requires the government to be liable in tort for its wrongdoing – resort to the labels of politics and policy provides no shield. The market substitution argument, meanwhile, has been dismissed by other judges. And an international agreement, not enacted in Australian law, does not provide a sound basis for denying liability.

The novelty at the heart of Sharma is that we are looking ahead to a world of climate harm. Negligence is ordinarily an after-the-fact proposition. Many of the cases cited during the hearing related to asbestos claims. They raise an interesting hypothetical: if we had known of the risk of mesothelioma at the time, would courts have acted? Surely it cannot be right to say that those who will suffer the foreseeable harm – whether from asbestos exposure or the climate crisis – must wait for the injury to arise before they can sue to stop it.

Ultimately, the persuasiveness at the heart of the teenagers’ argument is its simplicity. The law of negligence governs personal injury. If Ley allows 100 million tonnes of carbon dioxide into the atmosphere, she will be inflicting future harm on generations of Australians to come. That is the uncontested scientific evidence in Sharma – and no amount of legal sophistry can deny it. The federal court should not avert its eyes from the climate crisis.

• Kieran Pender is an Australian writer and lawyer. He is an honorary lecturer at the ANU College of Law