A landmark Supreme Court decision that reins in federal agencies’ authority is expected to hold dramatic consequences for the nation’s health care system, calling into question government rules on anything from consumer protections for patients to drug safety to nursing home care. The June 28 decision overturns a 1984 precedent that said courts should give deference to federal agencies in legal challenges over their regulatory or scientific decisions. Instead of giving priority to agencies, courts will now exercise their own independent judgment about what Congress intended when drafting a par…