The Trump administration on Tuesday proposed to repeal a 2009 landmark finding that greenhouse gases pose a threat to the public.

The "endangerment finding" came after the Supreme Court ruled in 2007 that the Environmental Protection Agency (EPA) can regulate greenhouse gases (GHG) if it determines that they harm Americans’ well-being.

But now, the EPA says it no longer believes that gases such as carbon dioxide harm the public.

Here are five things to know:

The finding determined that GHGs caused harm

In 2009, the Obama administration made two key determinations: that greenhouse gases including carbon dioxide and methane endangered public health and welfare, and that auto sector emissions played a part in that danger.

Now, the EPA is proposing to overturn that finding and instead determine “that there is insufficient reliable information to retain the conclusion that GHG emissions from new motor vehicles and engines in the United States cause or contribute to endangerment to public health and welfare in the form of global climate change.”

It underpins automobile regulations

The move to repeal the endangerment finding is not simply symbolic. It was a legal finding that underpins climate regulations, particularly those that pertain to cars and trucks.

The EPA’s proposal on Tuesday also seeks to repeal the nation’s car and truck regulations, meaning the agency is not requiring any set number of electric models on the market and that automakers’ fleets can emit as much as they would like.

It said that the move will have cost savings, but it is also expected to exacerbate climate change and pollutants.

The regulation did not explicitly address climate regulations from other sectors, but the EPA has separately proposed to remove all climate regulations from

© The Hill