Nearly two dozen Democratic-led states sued the Trump administration Wednesday over a new rule barring federal Medicaid funding for gender-affirming care for transgender youth.The lawsuit, filed Tuesday in federal court in Massachusetts, challenges a rule the Centers for Medicare & Medicaid Services issued last month barring states from using federal Medicaid or Children’s Health Insurance Program funds for what the agency calls “experimental and life-altering sex-rejecting procedures.”But the coalition of 21 states and Washington, D.C., alleges that CMS exceeded its legal authority by excluding otherwise lawful medical treatments from federal reimbursement.Related: Transgender federal workers sue Trump administration over insurance ban on their health care“Contrary to Congress’s clear directive, the Rule strips the states of their statutorily authorized role as Medicaid and CHIP administrators, usurps the states’ medical necessity determinations, and permits the federal government to unilaterally prohibit federal financial participation (“FFP”) or reimbursement for certain types of healthcare treatments and services,” the complaint states, “only when those treatments and services are provided to transgender adolescents. Congress has never empowered Defendants to do so.”Attorneys general from California, Colorado, Connecticut, Delaware, Hawaii, Illinois, Maine, Maryland, Massachusetts, Michigan, Minnesota, Nevada, New Jersey, New York, Oregon, Rhode Island, Vermont, Virginia, Washington and Wisconsin filed the lawsuit alongside Washington, D.C., and Pennsylvania Gov. Josh Shapiro.Administration officials have characterized gender-affirming care as experimental, despite the American Medical Association, the American Academy of Pediatrics and other leading medical organizations supporting access to the care and opposing government restrictions on it.Related: Republican states join Trump FTC in lawsuit against world’s leading transgender health