What is the difference between civil forfeiture and criminal forfeiture?

The classical distinction between civil and criminal forfeiture was founded upon whether the penalty assessed was against the person or against the thing. Forfeiture against the person operated in personam and required a conviction before the property could be wrested from the defendant. See Calero-Toledo, 416 U.S. at 682, 94 S.Ct. at 2091; One 1958 Plymouth Sedan v. Pennsylvania, 380 U.S. 693, 700, 85 S.Ct. 1246, 1250, 14 L.Ed.2d 170 (1965). Such forfeitures were regarded as criminal in nature because they were penal; they primarily sought to punish. Forfeiture against the thing was in rem and the forfeiture was based upon the unlawful use of the res, irrespective of its owner's culpability.

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