Source: http://www.wisconsinappeals.net/on-point-by-the-wisconsin-state-public-defender/state-v-richard-e-houghton-jr-2013ap1581-cr-petition-for-review-granted-11315/
Timestamp: 2019-04-18 16:53:16+00:00

Document:
Can a police officer’s reasonable mistake of law give rise to reasonable suspicion or probable cause necessary to uphold a seizure under article I, §11 of the Wisconsin constitution?
Police stopped Houghton’s car for two reasons: It lacked a front license plate; and the driver’s view through the windshield was supposedly obstructed by an air freshener and a GPS unit. But Houghton’s car was registered in Michigan, which doesn’t issue two plates, so the lack of a front plate didn’t violate § 341.15(1). Thus, as the state conceded, the first reason was based on a mistake of law, and the rule in Wisconsin is that a police officer’s mistake of law can’t justify a traffic stop—a rule the supreme court just reaffirmed last summer in State v. Brown, 2014 WI 69, 355 Wis. 2d 668, 850 N.W.2d 66.
But in December, in Heien v. North Carolina, 135 S. Ct. 350 (2014), the U.S. Supreme Court held that a “reasonable” mistake of law can justify a seizure under the Fourth Amendment. As discussed in more detail in our post on Heien, the holding in Brown rests on both the federal and state constitutions, so the question now becomes whether Wisconsin will interpret article I, § 11 of the Wisconsin constitution to provide more protection that the Fourth Amendment when it comes to a police officer’s mistake of law. Of course, Wisconsin usually conforms its search and seizure clause to the Fourth Amendment, so Houghton’s daunting task is to convince the court not to do so in this situation.
Even if the court decides to follow Heien, there’s still the separate question of whether the officer’s mistake of law in this case was “reasonable.” What that means isn’t clear from Heien itself, as our post on the case discussed, and unlike Heien the mistake in this case isn’t about the meaning of an ambiguous state statute, but instead involves what the law of a neighboring jurisdiction requires. Is it objectively reasonable for an officer to believe the other jurisdiction requires a front plate? Other courts have forgiven officers for making this kind of mistake, e.g., Travis v. State, 959 S.W.2d 32 (Ark. 1998), and People v. Glick, 250 Cal. Rptr. 315 (Ct. App. 1988), and we’ll now see if Wisconsin will follow suit.

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