Today, in U.S. v. Davis, the Sixth Circuit overturned a Michigan Statute prohibiting dangling objects from a rearview mirror that "obstruct the vision of the driver of the vehicle." A panel, with Judge Martin writing the opinion and citing Kolendar v. Lawson, 461 US 352 (1983), found the language of this statute was void for vagueness because it allowed for the "standardless sweep [that] allows policemen, prosecutors, and juries to pursue their personal predilections." Martin went on to observe that the void for vagueness doctrine is even more important now because:
the rule of law concerns underlying the vagueness doctrine are even stronger in
the Fourth Amendment context after the Supreme Court's decision in Whren v.
United States, 417 US 806 (1996), which did away with pretext analysis under the
Fourth Amendment. If courts cannot review the motives of law enforcement
officers after the fact, it is crucial that they review the breadth of discretionary
authority police receive from legislatures at the outset. The alternative is a broad
abdication of the judicial duty to enforce the Fourth Amendment's prohibition on
unreasonable searches and seizures at a time when this duty is more important
Davis, at *7.
Unfortunately for Mr. Davis, the void for vagueness doctrine rarely helps those challenging the statute first. The Sixth went on to find that "the good faith exception to the Exclusionary Rule applies to searches conducted in good faith reliance on a presumptively valid statute." citing United States v. Krull, 480 US 340 (1987) and Michigan v. De Fillippo, 443 U.S. 31 (1979).
I admit that our office does not challenge statutes as void for vagueness as often as we should. Given Martin's opinion, this doctrine seems like rich ground to challenge stops premised upon, usually, overbroad city ordinances. It might not result in suppression against your client, but challenging statutes under this doctrine would force cities and states to start drawing their criminal laws more narrowly and restricting the police discretion on the street.
NOTE: On New Year's Eve, the Sixth Circuit issued a one sentence order withdrawing the opinion in Davis. From a review of the Sixth Circuit website it appears that the State of Michigan has filed a Motion to Intervene under 28 USC S 2403, and FRAP 44, asking the court for permission to argue for the constitutionality of the law in question. I personally will admit that I was not familiar with FRAP 44 that requires an attorney who is challenging the constitutionality of a statute on appeal to alert the court clerk in writing that he is challenging the law, in order to give the clerk opportunity to alert the State in question of the challenge.