Source: http://www.wisconsinappeals.net/on-point-by-the-wisconsin-state-public-defender/scow-stop-and-search-of-car-based-on-officers-misunderstanding-of-tail-lamp-statute-violates-4th-amendment/
Timestamp: 2019-04-21 03:02:12+00:00

Document:
Another defense victory! Police stopped Brown’s car due to an alleged violation of §347.13(1), which prohibits the operation of a vehicle at night unless its tail lamps are in “good working order.” In a 4-3 decision, the majority holds that the police here misunderstood the statute, so the stop was illegal. Furthermore, a stop based upon an officer’s mistake of law, is unlawful, and the results of the ensuing search must be suppressed. Justice Prosser, dissenting, predicts the majority’s interpretation will be “a bonanza for litigants seeking to challenge motor vehicle stops.” ¶79.
¶42 In sum, we do not interpret Wis. Stat. § 347.13(1) as requiring every single light bulb in a tail lamp to be lit. The plain language of the statute requires that a tail lamp emit a red light visible from 500 feet behind the vehicle during hours of darkness. This interpretation is further supported by related statutes requiring that the lamps be in proper working condition.
The State conceded that if the officers misinterpreted the law, then the stop would be illegal because a lawful stop cannot be based upon a mistake of law. See State v. Longcore, 226 Wis. 2d 1, 593 N.W.2d 412 (Ct. App. 1999). That concession, bolstered by loads of supporting decisions from around the country, sealed the State’s fate. See cases cited at ¶¶23-25. But it sure didn’t cinch a unanimous decision.
Justice Prosser’s dissent took issue with the majority’s reading of §347.13(1). “The majority opinion significantly dilutes the meaning of ‘proper working condition’ and ‘good working order’ in the lighting equipment statutes,” he wrote. ¶74. “It has seriously impaired law enforcement’s ability to stop vehicles to alert the drivers of equipment defects.” ¶78.
¶79 Now that law enforcement officers are precluded from pulling over vehicles with flawed tail lamps if the tail lamps are visible from 500 feet, there is likely to be a bonanza for litigants seeking to challenge motor vehicle stops. The uncertainty in the law will create difficulties for law enforcement and new burdens on circuit courts.
Justice Roggensack (joined by Justice Ziegler) assumed arguendo that the majority’s interpretation of §347.13(1) was correct. She rejected the idea that an officer’s mistake of law renders the stop illegal–a point the State had conceded.
¶114 . . . I conclude that the legality of a stop depends on whether under the totality of the circumstances a reasonable officer could have believed that a law violation was occurring. See Martin, 411 F.3d at 1001 (a search is valid when “an objectively reasonable police officer could have formed a reasonable suspicion that [a defendant] was committing a . . . violation”). Therefore, “in mistake cases[,] the question is simply whether the mistake, whether of law or of fact, was an objectively reasonable one.” Smart, 393 F.3d at 770. I further conclude that under the totality of the circumstances a reasonable officer could have believed that Brown’s tail lamp violated § 347.13(1).
As On Point recently reported, SCOTUS just grant certiorari review in a case like this one. See our post in Heien v. North Carolina here. The issue in Heien is whether a police officer’s mistake of law can provide the individualized suspicion that the Fourth Amendment requires to justify a traffic stop. In these circumstances–where SCOW has just decided a constitutional question that is pending before SCOTUS–one might expect to see the State file a cert. petition. That would be rather awkward in this case due to the State’s admission that a traffic stop based upon a mistake of law is unconstitutional.

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