Intentionally lying about income to boost your Obamacare tax credits could get you into hot water — $25,000 to $250,000 of hot water. That's a key takeaway from guidance recently released by the Obama administration. The tax credits that subsidize insurance from the state exchanges operate on a sliding scale; people with lower incomes receive bigger tax credits. The administration previously made it clear that people who under-report their income and receive subsidies that are too generous will be required to refund the federal government at tax time. Under-reporting is only part of the story, though. In states that don't expand Medicaid, there's a coverage gap for the uninsured living below the poverty line (about $11,670 for an individual).