Federal drug-enforcement officials have made it a serious felony for doctors to overprescribe painkillers or, as the applicable law states, to prescribe controlled substances “other than for a legitimate medical purpose and in the usual course of professional practice.” But the line between legitimate and illegitimate prescription—as drawn by the Drug Enforcement Administration (DEA) and the Justice Department—is far from clear. This puts physicians in great legal jeopardy, and too often leaves their patients to suffer needless agony.

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