The fraud squads that look for scams in the federal Medicare and Medicaid programs have some new weapons: tools and funding provided by the Affordable Care Act. The federal health law and other legislation directed the federal government to start using sophisticated anti-fraud computer systems. Peter Budetti, who oversees anti-fraud efforts at the Centers for Medicare and Medicaid Services, said the systems, which are being used first with Medicare, are similar to those used by credit card companies to detect suspicious purchases. The computer program crawls around the heaps of Medicare claims—some 4 million a day—to look for outliers. And for the first time, doctors and others who want to bill Medicare are being assessed based on their risk to commit fraud. Those who seem crooked are kept out.