AUSTIN (CBSDFW.COM) — Justices on the U.S. Supreme Court are set to hear oral arguments on the Texas-led challenge to the Affordable Care Act — also known as Obamacare.

Texas is leading a coalition of Republican states who argue the ACA’s individual mandate is unconstitutional and that the act should be struck down in its entirety.

The 2010 health care law offers benefits for about 21 million Americans, including some 1 million in Texas who have subsidized health insurance plans under the law.

The law includes protections for those with pre-existing conditions, allows parents to keep their children on their health insurance plans until the age of 26, offers no-cost benefits for certain health services and expands Medicaid to low-income adults.

Experts have voiced concerns about ending the law without a replacement, particularly during the COVID-19 pandemic. The impact in the Lone Star State could be especially harsh since the state of Texas has the nation’s highest uninsured rate.

In 2012, Chief Justice John Roberts, joining with the court’s four liberals, upheld Obamacare by calling the law’s individual mandate a tax. But in 2017, the GOP-led Congress cut the tax penalty for those who lacked insurance to zero.

Led by Texas, Republican-led states sued, arguing that since the mandate was no longer tied to a specific tax penalty the mandate is  unconstitutional, as the “change made it impossible to fairly interpret” the provision as a tax. They also argued that because the individual mandate was intertwined with a multitude of other provisions, the entire law should fall. The Trump administration agrees the law should be declared invalid.

California and other Democratic-led states are defending the law, along with the Democratic-led House of Representatives.

The blue states warn of “prolonged uncertainty” about the future of Obamacare makes it more difficult for individuals, businesses and state and local governments to make decisions in reliance on the law, “threatening adverse consequences for American families, healthcare markets and the broader economy.”

Texas first brought the challenge to Obamacare in February 2018, and a federal district judge in the state struck down the full law as unconstitutional later that year. Then, in December 2019, a three-judge panel on the 5th U.S. Circuit Court of Appeals found the individual mandate unconstitutional, but sent the dispute back to the lower court to determine whether the rest of the law could stand without it.

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