In what people are calling the “Trial of the Century,” a group of kids aged 9 to 20 are suing US president Donald Trump and the federal government for gross incompetence when it comes to protecting the environment and dealing with climate change.

If successful, this lawsuit could usher in sweeping new regulations to safeguard the health of the planet.

“Our case is a direct constitutional challenge to a Trump administration at war with the reality of climate change and bent on pushing a deadly fossil fuel agenda at the expense of its citizens’ safety and human rights,” said Jacob Lebel, 20-year-old plaintiff from Roseburg, Oregon, in a statement from the group.

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“Climate science, not alternative facts, will determine the outcome of our court trial and that gives me hope for my children's generation and the future of this country,” the statement read.

While Trump seems like an obvious opponent for the plaintiffs because of his past climate denialism, the lawsuit actually began against former president Barack Obama.

Two years ago, the kids, known as the Earth Guardians and supported by Our Children’s Trust, lodged a protest against Obama and the government.

The government tried to have the case dismissed but were denied in 2015. Then in late 2016, the plaintiffs were permitted to proceed with the lawsuit by a US district judge.

"Climate science, not alternative facts, will determine the outcome of our court trial and that gives me hope for my children's generation and the future of this country."

It’s a dramatic charge that has the potential to completely rewrite basic assumptions about government — what, after all, are its obligations to the people? It also raises fundamental questions about human rights. The plaintiffs argue that their basic human right to a clean, safe, and sustainable environment is being violated by none other than the government for failure to enact strong regulations.

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By promoting the development and extraction of fossil fuels, funding and certifying fossil fuel infrastructure, providing subsidies and tax breaks to the fossil fuel industry, using fossil fuels in various agencies and departments (especially the defense department), and many more minor and major actions, the federal government has played an enormous role in accelerating climate change.

The case ultimately rests on the principles of the public trust doctrine and substantive due process, according to the San Francisco Gate.

According to these concepts, the government must protect public resources and it cannot deny or obstruct a person’s right to life, liberty and property without due process.

Climate change threatens to undermine all of these legal obligations by radically altering the physical world and posing an existential threat to many people’s lives.

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The Trump administration, aligned with the Republican-controlled legislature, have hinted at a massive sale of public lands and a halt to efforts to combat climate change.

These anti-environment priorities significantly elevate the stakes of the trial.

Trump has faced dozens of lawsuits since taking office, but this lawsuit could be the one that has the biggest effect on his presidency.

“We want our children to look back in the textbooks and say, ‘Oh, our parents’ generation — they really fought for us,’ ” said Victoria Barrett, 17, to The New York Times.