Is detention for the purpose of preventing future crime a punishment?

1 It is arguable that, with respect to those accused of crime, pretrial detention imposed solely for the purpose of preventing the commission of future crimes prior to trial is punishment. With respect to those convicted of crime, the imposition of added confinement, beyond the penalties for the specific offense, is nonetheless punishment despite the prospective purpose of preventing future harm. Specht v. Patterson, 386 U.S. 605, 608-09, 87 S.Ct. 1209, 1211-12, 18 L.Ed.2d 326 (1967). The extension of that principle to those accused of crime raises the broad issue of whether pretrial detention to prevent future crime is ever permissible, an issue that need not be faced in deciding this case. For purposes of this appeal, I am willing to assume that pretrial detention ordered for the purpose of preventing future crime serves a regulatory purpose.