Summary: Pursuant to a congressional request, GAO reviewed the proposed Health Coverage Availability and Affordability Act's fraud and abuse provisions. GAO noted that: (1) unlike a previous bill, the proposed legislation does not make it more difficult to prove criminal liability for making kickbacks for service referrals, but it does continue to propose significant enforcement curtailment under certain Medicare civil monetary penalty provisions by eliminating the due diligence standard for claims; (2) both bills place a number of new antifraud and antiabuse administrative responsibilities on the Department of Health and Human Services (HHS), but the new bill provides additional resources needed to fund the new duties; (3) the proposed legislation does not reduce the savings from the prohibition against physician self-referrals; (4) the bill excepts some individuals or entities from criminal liability for referral kickbacks if they are at a substantial financial risk for the services or items provided; (5) not all the listed risk arrangements maximize the participants' financial risk from unnecessary services; (6) the bill requires HHS to issue binding advisory opinions on the legality of arrangements or activities that could be subject to criminal or civil penalties under antifraud and antiabuse provisions, but HHS believes that such opinions are meaningless, since it cannot determine the intent of the requestors; and (7) the HHS advisory opinion provisions would also decentralize the Department of Justice's single authority for enforcing criminal laws.