CHICAGO (CBS)– The U.S. Supreme Court will hear arguments, Tuesday, about the future of the Affordable Care Act, known as Obamacare.

Many Chicagoans may be impacted by the decision.

Depending on the outcome of the case, more than 23 million people could lose their health insurance. But while the hearing begins Tuesday, a decision isn’t expected for months.

The Trump administration and Republicans have been trying to get rid of the 10-year-old health care law for years now. Eight years ago, the Supreme Court’s ruling left important parts of the law intact.

But, the court is now controlled six-to-three by a conservative majority.

Protections for people with pre-existing conditions and coverage of young adults up to age 26, under their parents’ insurance policies, are all at stake.

Tuesday also marks the first time Justice Amy Coney-Barrett will be on the bench since she was sworn in.

President-elect Joe Biden plans to deliver a speech on the Affordable Care Act Tuesday as the high court hears arguments on its merits.

A decision isn’t likely until spring of next year.

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