How the science won in Federal Court

Earlier this year, eight teenagers and a nun took the Federal Minister for the Environment to court. This may sound like the start of a fairly bad joke, but the case was actually a remarkable step forward in climate legislation – because the Federal Court ruled late last month that the minister has a duty “to take reasonable care to avoid causing personal injury” to future generations. 

Notably, the case needed to bring science into the equation to understand just how much climate change will impact today’s children in the future. This scientific expertise came from an expert witness, Dr Karl Mallon from the consultancy firm Climate Risk, whose analysis was instrumental in Justice Bromberg’s ruling.

Several other recent court cases around the world have also revolved around climate change, including a Dutch court’s ruling that oil giant Shell needs to halve their emissions by 2030.

But the science describing the impacts of the climate crisis has been solid for decades – so why is the law only just taking notice? How crucial is science in legal decision making, and how can evidence from a discipline as broad and complex as climate science be presented in court?

To gain insight into these tricky questions, Cosmos spoke to two experts: Mallon, who has worked in the climate change policy and technical space for more than 25 years, and Jacquie Svenson, a solicitor at the University of Newcastle Legal Centre who specialises in public environmental interest cases.


In review: Sharma v Minister for the Environment

Karl Mallon
  • The case was brought to court by eight teenagers and their litigation representative, 86-year-old nun Sister Marie Brigid Arthur.
  • They were attempting to block a proposed extension to Whitehaven’s Vickery mine in northwest NSW by running a negligence case – arguing the Minister for the Environment, currently Sussan Ley, has a duty of care to protect future generations from harm.
  • The case called on Mallon’s expertise to estimate the extent to which climate change would harm children in Australia.
  • Though the injunction to stop the mine was not granted, the judge ruled that the Minister does in fact have a duty of care.

How is science presented in court?

Solicitor Jacquie Svenson has been involved in climate space since the mid-2000s, when she worked at the Environmental Defenders Office, and she says that using scientific evidence in these cases is “bread and butter, really”.

But that doesn’t mean that it’s easy. Science and the law are two completely different realms – with different languages, cultures, processes and desired outcomes. 

Jacquie Svenson

“The nub of the issue is the fact that science is based on uncertainty, or on the notion that you’re trying to disprove – not prove – something, whereas the law is trying to do the opposite,” Svenson explains. “There’s often a crunch between the two disciplines just on that basis.”

She says that in the eyes of the law, scientific evidence is always considered opinion – “because the court is not expert enough to be able to decide whether or not what the science is saying is true”.

This “opinion” is usually brought before the court by an independent expert, once one side has established that such an expert is necessary. This person needs to be appropriately qualified for their word to be accepted by the court, and the opposing side can question that person’s credibility before they give evidence.

In Sharma v Minister for the Environment, Mallon was called on as this expert based on his work in climate change risk analysis. His consultancy firm Climate Risk advises governments and businesses around the world about how extreme weather and climate change may affect built assets and communities.

“It’s the first time I’ve been an independent expert in a court case, and it was an interesting learning curve,” Mallon says.

Back when he was doing his PhD, Mallon recalls that one of his professors was often called on as an expert: “[He] was always going off and doing analyses – he’d be dropping motorcycle helmets from the roof to see how they cracked, or dropping boats into tanks of water to see what happened, things like that.”

Mallon’s experience was quite different – his analyses involved extensive climate data and modelling instead of motorcycle helmets.

But what was really unexpected, he notes, was the difference in communication styles. In science, it’s all about the evidence base, the transparency of methods and the repeatability of the experiment. 

“In the end a lot of it was: ‘You’re the expert, what’s your opinion?’ And that was quite confronting.”

Karl Mallon

“You’re not believed because of who you are, even if you’re Einstein,” Mallon says. “You’re believed because of what you’ve set down, whether it’s your mathematics or experimental results or statistical analysis.”

But in a court case, it’s all about an individual’s opinion.

“You can support your opinion,” Mallon adds. “We just did what we always do, which is provide a supporting report with all of the evidence, all the analysis, all the mathematics – but in the end a lot of it was: ‘You’re the expert, what’s your opinion?’ And that was quite confronting.”

The supporting report that Mallon presented (which itself is quite confronting – read it here) was based on a series of questions given to him by the court, revolving around the fairly vague question: “What would be the future harm to children in Australia from climate change?”

Mallon and the Climate Risk team set out to provide answers that were quantifiable – such as how much harm? And what kind?

They used the Intergovernmental Panel on Climate Change’s high-end emission scenario (RCP8.5 – the only one consistent with increasing coal production) along with atmospheric modelling to quantify the financial and health costs that today’s young people will face throughout their lives.

The kinds of numbers the team was able to produce were surprising to some, Mallon notes: “I know that the legal team were very surprised. They didn’t know that some of the stuff we do is possible.”

The team had to make some choices about what kinds of information they wanted produce and how to present it in a format that the judge would understand and consider. 

Key findings include the average loss to the value of family homes by 2030 ($41,000–85,000 per child); the loss of income throughout a young person’s working life due to rising temperatures causing a drop in productivity ($75,000); and the percentage of today’s young people who will require hospitalisation from heat stress in their senior years (20%).

“I’m still a scientist and an engineer at heart. I don’t want you to believe me because I’m Karl…If you don’t believe me, just redo the numbers yourself.”

Karl Mallon

Despite the meticulous evidence-based work that went into producing these numbers, in the end what mattered was Mallon’s opinion.

“But I’m still a scientist and an engineer at heart,” he says. “I don’t want you to believe me because I’m Karl. I want to prove to you that if you put A, B and C together you’re going to get an answer, and this is what the answer looks like. If you don’t believe me, just redo the numbers yourself.”

How did the deliberation process work?

Mallon notes that he watched some of the deliberations in the courtroom – and his respect for lawyers increased.

“To some extent, our work was to establish that there was a quantifiable harm to children, where we could…connect, let’s say, a coal plant through to that harm via things like emissions policies, physical climate change impacts and global circulation models,” he explains. 

“That was our job, but the job of the lawyers was to use – in this case – the common law framework to create a similar connection between a decision [and] the responsibilities of a minister.”

It was tricky to establish this causal chain, he says – far more complex and less linear than he expected. 

Regards a court action, Mallon confesses he always had the view that one side comes along and argues its approach; then then other side comes along and argues its approach; and then the judge wanders off and decides which is right.

“Whereas what I saw was very, very detailed technical negotiations over law,” he explains. “I watched barristers and the judge not so much argue but really tease out what previous judgments meant and how they apply to the case. It was like watching two philosophers debating, or you could even see it [like] two scientists arguing…”

“The nub of the issue is the fact that science is based on uncertainty, or on the notion that you’re trying to disprove – not prove – something, whereas the law is trying to do the opposite.”

Jacquie Svenson

You’re in a realm, he says, where “the fundamental basis is not agreed – you are trying to work that out”.

He was essentially watching innovation, watching the law change: “Watching very clever people really establish a rationale, in a way that I’m not used to.”

“I’m used to mathematics, and at the end of the day you get to a point where you get a right or a wrong, or you get some kind of statistical view of truth – whereas these guys were operating in what is essentially an abstracted realm of rationale, of law, which is obviously a human creation…

“It’s a bit like watching them invent some new maths – it’s like, ‘right, we don’t have a way of solving this problem, so we’re going to have to invent some rules which will help us navigate this’.”

What was the response to the scientific evidence?

Interestingly, Mallon’s reputability – and his opinion – were not questioned in court, and his evidence was accepted wholesale.

“I got away lucky because none of the evidence I presented was contested, which was unusual,” he says – guessing that it may be because his work is very specialised, or because it’s already implicitly trusted as his company provides reports and analyses for government and the private sector.

Whatever the reason, Svenson agrees that it’s significant.

“Because the court is not a scientific expert…ultimately what can then happen is anything the scientists say is kind of gospel, because they’re the experts – so there’s a whole kind of covert war that goes on to try and prevent them from having credibility,” she explains.

But Mallon’s opinion was accepted by both the judge and the federal government’s legal team – which is an important shift.

“That then means that becomes a fact for those people,” Svenson explains. “The doubt about climate impacts being real was effectively done away with in that narrow circumstance by the court saying it is reasonably foreseeable that these children will be affected by the decision of the Minister to approve the coal mine.”

Previously, in the eyes of the law, the science was up in the air – “but now the Federal Court has said yes, it’s a no-brainer”, she summarises.

What impact will this have?

The decision regarding the Minister’s duty of care is not legally binding, as it was only a finding made in the course of another decision – which means it has not yet been found to be a fundamental legal truth.

“But,” Svenson says, “what is significant about it, and this is what I’ve seen in the past, is that even though they lost on a technicality, all ministers will take notice of that decision – that is, that they have a duty of care to future generations in the decisions that they make – and they will act as though it is binding.”

It’s also worth noting that in cases such as this, the government is able to come in and pass legislation that overturns the case, reversing the positive outcome. 

“That happens all the time,” Svenson says; she thinks it’s one reason why people are getting more creative in the kinds of cases they bring regarding climate change.

Of course, the scientific grounding for the impacts of climate change has been solid for a long time – and Svenson says that “people have been trying to put this economic stuff and this scientific stuff before courts for decades, but because the gates are so well-guarded…the traditional ways haven’t worked”.

In the case of Sharma v Minister for the Environment, someone realised that since the minister has approval power, that gives rise to a duty of care, and so they went down the creative route of running a negligence case.

This creativity is key to moving forward, because the old ways aren’t working; it is, Svenson says, quite frustrating to use the law to address massive and pressing environmental issues.

“You’re forever going in and trying to use instruments not designed for purpose,” she says.

She often runs review cases where she argues against a development by saying that a certain assessment didn’t happen – but she’s not really trying to get the assessment done, but rather prevent the development from happening at all. 

“But I use that argument because that’s all I’ve got – because the law doesn’t give me anything else,” she says. “Or the law says it’s illegal to harm a threatened species, but how do I prove that’s what’s happened? The resources required to establish that are so enormous, and there are so many exceptions.”

“Because the court is not a scientific expert…ultimately what can then happen is anything the scientists say is kind of gospel, because they’re the experts – so there’s a whole kind of covert war that goes on to try and prevent them from having credibility.”

Jacquie Svenson

The law is in no way leading on climate or environmental issues. In fact, Svenson says, the law comes last.

“There will be a law to protect something only when it’s so obvious it has to happen,” she says. “The law doesn’t lead… The science showing that it’s crucial, and the social licence for what it’s trying to achieve, are much more important.”

Mallon says that he sees the law as a litmus test.

“It will be easy for the government to either overturn one of the decisions, or appeal…or change the law so that they get rid of the duty of care,” he says. “But the extent to which the public mood has shifted will indicate the extent to which they fight tooth and nail.

“I think however much we want politics and law to be separated, a lot of what’s acceptable in a judgement will depend on the public mood…what the public expects of justice, and how justice is served.”

Svenson, too, thinks that it’s inevitable that a shifting social consciousness around environmental issues will affect decisions made in the legal sphere. 

“Judges would never admit that,” she says, “but there’s always a public policy dimension to how they decide things. Judges are allowed to take into account the public interest…and how that’s expressed and articulated by any given society changes over time. Certainly climate concerns are much more apparent than they were 20 years ago.”

What does the future of environmental litigation look like?

Legal firms just running climate litigation are beginning to pop up everywhere, and people are becoming more resourced and more creative.

“I think people are just getting more committed…giving up their cushy law jobs to go do that stuff now, in a way that it wasn’t seen as urgent 10 years ago,” Svenson says. “We’ve got until 2030, the IPCC said, [so] we’ve just got to get our skates on and throw everything to it.”

She predicts that there will be more successful cases in the future, which will trigger a bigger shift.

“Then laws will get changed so that stuff’s not necessary anymore,” she says. “That’s usually what happens. It’s that notion of social change – it’s fought against, and laughed at, and then treated as though it was always thus.

“In 10 years’ time, I’m hopeful it will become a no-brainer that we no longer dig up fossil fuels from the ground in great quantities in Australia – so that stuff won’t need to be litigated anymore, because there’ll be a flip. It will look as though it’s impossible, impossible, impossible – and then suddenly it’ll flip and everyone’s doing it.”

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