Two years ago Steven D. Ballinger of Collinsville, Illinois, was sentenced to two and a half years of probation in state court after he pleaded guilty to sexual abuse and child pornography charges stemming from his videotaped encounter with a 12-year-old girl in July 2006, when he was 26. Last Friday he was sentenced to 30 years in prison for the same crime, this time in federal court. A federal prosecutor explained that U.S. Attorney Steve Wigginton was "very offended by what he perceived as an extremely lenient sentence for this type of crime."While Wigginton's reaction is understandable, do we want to let prosecutors try a defendant again whenever they think he got off too lightly the first time around? Isn't that sort of serial prosecution barred by the Fifth Amendment's Double Jeopardy Clause? Not, according to the Supreme Court, if it involves two different levels of government. According to the "dual sovereignty" doctrine, even though Ballinger pleaded guilty to the same crime (producing child pornography) both times, the fact that it was a state offense the first time and a federal offense the second time means the Double Jeopardy Clause does not apply.