Michigan, Colorado, Nevada and Iowa are seeking to join the federal lawsuit Texas v. USA to defend the ACA's constitutionality.
The four states must receive permission from the court to join 16 other states and the District of Columbia that want to uphold the healthcare law.
"The ACA provides important protections — including protecting people with pre-existing conditions — and access to healthcare for hundreds of thousands of residents in Michigan," Michigan Attorney General Dana Nessel said in a press release. "We have a strong interest in ensuring that the strongest possible arguments are presented in support of the ACA."
The lawsuit was brought by 20 states and claims the ACA was rendered unconstitutional when the individual mandate penalty was eliminated under the 2017 tax bill. A federal judge ruled the ACA unconstitutional in December and a group of state attorneys general appealed this ruling Jan. 3. The partial government shutdown put the lawsuit on hold.
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