Proposition 47 is a California voter initiative that reduced possessory drug offenses and minor thefts from felonies to misdemeanors. The law allows individuals to retroactively reclassify their convictions and mandates that these convictions shall be considered misdemeanors “for all purposes.” Under California law, reclassified convictions cannot be predicate felonies for future state sentencing enhancements. However, federal courts have held that reclassified convictions still constitute prior convictions for federal sentencing enhancements. Thus, these convictions still trigger felony-based enhancements. This Comment argues that this result is not mandated by Supreme Court precedent and that it conflicts with California’s intent to ameliorate the effects of prior felony convictions. Proposition 47 presents a novel situation—a retroactive state law that broadly alters the underlying conviction. Under principles of comity and federalism, federal courts should give full effect to Proposition 47 and similar state laws in federal sentencing.