Healthcare law could vex IRS as it tries to enforce penalties

The Supreme Court's decision to uphold most of President Barack Obama's healthcare law will come home to roost for most taxpayers in about 21/2 years, when they'll have to start providing proof on their tax returns that they have health insurance. That scenario puts the Internal Revenue Service at the center of the debate, renewing questions about whether the agency can police the healthcare decisions of millions of people in the United States while also collecting the taxes needed to run the federal government.