Lynn Webster, a Utah anesthesiologist, has spent the past decade writing and lecturing about how to safely prescribe opioids, as use of the drugs exploded in the U.S. He created a widely used screening tool to identify patients at risk for abusing them. Last week, he spoke to a federal panel about proposed limits on medications containing hydrocodone that he fears might hurt patients like Tuft. But the 62-year-old is also under federal scrutiny. The U.S. Drug Enforcement Administration is investigating overdose deaths of patients of his former pain clinic. And a U.S. Senate Committee on Finance is examining payments he's received from opioid manufacturers as president-elect of the industry-backed American Academy of Pain Medicine.