AUGUSTA, Maine — A group of 31 state Democratic lawmakers signed a legal document Wednesday in support of the federal health reform lawThe legislators joined 452 signers from 49 states in backing the constitutionality of the federal Affordable Care Act in a lawsuit before the U.S. Supreme Court. The document, known as an amicus, or “friend of the court” brief, was organized by the Progressive States Network and Constitutional Accountability Center. An amicus brief allows people and organizations who are not party to the case on appeal to submit their thoughts to justices.

Maine last January joined a multistate lawsuit against the federal health care overhaul, which challenged a provision mandating that all citizens purchase health insurance. In August, a federal appeals court struck down the so-called individual mandate but did not invalidate the overall law. The U.S. Supreme Court is expected to issue a ruling in June.

Rep. Sharon Treat, D-Hallowell, has led the effort in Maine to sign the brief. “I look forward to 2014 when insurance will be even more affordable and easier to purchase through the state-based health exchange marketplace, which the law creates,” she said in a statement. “I don’t understand why we would want to reject millions of dollars in tax credits for hardworking Maine people so that they can purchase health insurance, nor why we would reject the insurance marketplace that small businesses will be able to use to compare policies and shop for affordable coverage.”