Mostly known for her advancement of gender equality, the late U.S. Supreme Court Justice Ruth Bader Ginsburg was also known as a steady vote for environmental interests who argued before the high court.

She wrote opinions that created citizens’ rights to sue polluters under the Clean Water Act and the government’s right to regulate cross-state air pollution.

In 2014, she wrote a majority opinion supporting the EPA’s Clean Air Act rule requiring 28 states to slash power plant emissions that cross their borders. This ruling revived a 2011 EPA rule known as the Cross-State Air Pollution Rule and urged 28 states to start reducing their emissions.

She also authored the majority ruling that re-confirmed the EPA’s jurisdiction over greenhouse gas emissions in American Electric Co., Inc. v. Connecticut.

In this case, eight states alleged that four utility companies were a public nuisance because their CO2 emissions contributed to climate change. The companies argued that the EPA, not states, should oversee emissions standards. The court unanimously agreed that regulations on carbon emissions should be determined by the EPA by way of the Clean Air Act.

The historical case, Massachusetts v. EPA, which saw Ginsburg in the majority, found that the federal government has the authority to regulate greenhouse gas emissions as “air pollutants’ under the Clean Air Act and was the high court’s first-ever ruling on climate change.

Before her appointment to the U.S. Supreme Court, Ginsburg served on the U.S. Court of Appeals for the District of Columbia Circuit after she was appointed by former President Carter.

Ginsburg started her career in academia. She taught at Rutgers University and her alma mater Columbia Law School, where she transferred from Harvard Law School after her husband, Martin Ginsburg, took a job in New York City.