Demarco McDonald was arrested for possession of a firearm by a felon, in violation of 18 U.S.C. § 922(g)(1). Police found a gun in his car when they stopped him for using his turn signal while rounding a bend in a street. After the district court denied his motion to suppress evidence seized as a result of the stop, McDonald entered a conditional guilty plea reserving his right to appeal the denial of his motion to suppress. McDonald contends on appeal that his use of the turn signal was not illegal under Illinois law and that a police officer’s mistaken belief about the law could not support probable cause for his arrest. We agree and therefore reverse the decision of the district court.
I. BACKGROUND
On November 20, 2004, Belleville, Illinois police officers Michael Pearce and Timothy Lay stopped McDonald’s car after they received an anonymous tip and believed McDonald fit the description. As Officer Pearce approached McDonald, he noticed a gun on the floor of the car. Because McDonald had previously been convicted of a felony, he was charged under § 922(g)(1) for being a felon in possession of a firearm. McDonald moved to suppress evidence pertaining to the gun, initially arguing that the officers should not have pulled him over because the anonymous tip alone was not sufficient evidence to provide probable cause to stop him. The government responded, however, that McDonald was actually stopped because he used his turn signal but never turned onto a different street. The officers believed that was a traffic offense under 625 111. Comp. Stat. 5/ll-804(d) (2005). McDonald responded that § 5/11— 804 did not prohibit his actions and that Officer Pearce’s mistake of law could not justify a traffic stop.
Officer Pearce testified at the hearing on the motion, stating that the police received a tip claiming that a black male driving a maroon Buick possessed drugs and a handgun. Later that night, the officers saw a car matching that description and began to follow it. When the driver flashed his turn signal at a ninety-degree curve in the road where the road changed names, Officer Pearce stopped the car. He testified that he consulted his “Offense Code Book” (a guide for police officers that catalogs traffic laws), which listed an offense for “Improper use of turn signal” — the book contained a citation to *960 § ll-804(d) but provided neither the statutory language nor any further description of the offense. Officer Pearce concluded that McDonald did not need to use his turn signal at the bend in the road and that he must have improperly used the signal.
The district court ruled that the anonymous tip would probably not have been a sufficient ground to stop McDonald, but that the stop was warranted because Officer Pearce reasonably believed McDonald’s use of the turn signal was a violation of state law. The district court also stated in a footnote that although the statute does not specifically proscribe McDonald’s use of the turn signal, “it could, arguably, be so interpreted.” The court denied the motion to suppress. McDonald then pled guilty, but reserved his right to appeal the denial of his suppression motion.
II. ANALYSIS
On appeal, McDonald reiterates his argument that the officers stopped him based on an incorrect interpretation of the law, and that a mistake of law cannot support probable cause. We review a district court’s determination of probable cause de novo and its underlying factual findings for clear error.
United States v. Breit,
Police can stop an automobile when they have probable cause to believe that the driver violated even a minor traffic law.
United States v. Muriel,
The government maintains that it had probable cause to stop McDonald because Officer Pearce reasonably believed McDonald was violating § 5/ll-804(d). We are not aware of any decision in which an Illinois court has considered whether a driver who continues to proceed on the same street after engaging his or her turn signal violates § 5/11 — 804(d). We must, therefore, analyze the issue as we expect the Illinois Supreme Court would if it were deciding the case.
Carter v. Tennant Co.,
The statute states that a car’s “electric turn signal device ... must be used to indicate an intention to turn, change lanes or start from a parallel parked position.” § 5/11 — 804(d). The statute also provides that the signal “must not be flashed on one side only on a parked or disabled vehicle or flashed as a courtesy or ‘do pass’ signal to operators of other vehicles approaching from the rear.” Id. The statute does not state, however, that a driver must turn onto a different road once the turn signal is activated.
The government has not provided any evidence that § 5/11 — 804(d) was intended to address McDonald’s act of proceeding on the same street after engaging his sig
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nal at a bend in the road. In an analogous case, the Fifth Circuit interpreted a Texas statute with similar language,
1
ruling that “a plain reading of the Code provisions at issue does not support the view that having a turn light on without turning or changing lanes is a violation of Texas law.”
United States v. Miller,
Officer Pearce was thus mistaken in his belief that McDonald’s conduct violated the law, and now we must consider whether the officer’s erroneously held belief could nonetheless provide probable cause to justify the stop. Although we have not yet addressed the issue, several other circuits have determined that even a reasonable mistake of law cannot support probable cause or reasonable suspicion. In
Miller,
the Fifth Circuit determined that because driving straight with an engaged turn signal is not a violation of Texas law, “no objective basis for probable cause justified the stop.”
Miller,
We agree with the majority of circuits to have considered the issue that a police officer’s mistake of law cannot support probable cause to conduct a stop. Probable cause only exists when an officer has a “reasonable” belief that a law has been broken.
Muriel,
It makes no difference that an officer holds an understandable or “good faith”
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belief that a law has been broken. Whether the officer’s conduct was reasonable under the circumstances is not the proper inquiry.
See Chanthasouxat,
By all indications, Officer Pearce genuinely believed McDonald had violated the law when he did not turn onto a different road after engaging his signal. As the government highlights, the Offense Code Book Officer Pearce consulted at the time of the stop listed improper use of a signal as a violation, and it did not provide the statute’s text. Moreover, no reported case had addressed whether conduct similar to McDonald’s violated § 5/11 — 804(d).
Even though Officer Pearce may have acted in good faith, there is no good faith exception to the exclusionary rule when, as here, an officer makes a stop based on a mistake of law and the defendant is not violating the law.
Chanthasouxat,
Finally, we note that the mistake of law at issue here is distinguishable from the circumstances in several cases cited by the government where an officer stopped a defendant based on a reasonable belief about a fact that later turned out to be wrong.
See Muriel,
Because the officers here did not have probable cause to stop McDonald, the district court should have granted his motion to suppress.
III. CONCLUSION
Accordingly, the district court’s decision is Reversed and we Remand for further proceedings consistent with this opinion.
Notes
. The Texas statute states:
(a) An operator shall use the signal authorized by Section 545.106 to indicate an intention to turn, change lanes, or start from a parked position.
(b) An operator intending to turn a vehicle right or left shall signal continuously for not less than the last 100 feet of movement of the vehicle before the turn.
(c)An operator may not light the signals on only one side of the vehicle on a parked or disabled vehicle or use the signal as a courtesy or 'do pass’ signal to the operator of another vehicle approaching from the rear.
Tex. Transp. Code Ann. § 545.104 (Vernon 1997).
