It may sound un-American, but police can stop you for an alleged traffic infraction that they haven’t even seen. The Fourth Amendment to the United States Constitution permits brief investigative stops where law enforcement has “a particularized and objective basis for suspecting the particular person stopped of criminal activity.”

This sounds reasonable enough, at least until you realize that the officer’s particularized and objective basis for suspicion doesn’t need to be grounded in anything that the officer has actually observed—it can be based entirely on an anonymous tip. Whether an officer’s suspicion based on such a tip is constitutionally reasonable officially depends on: (1) the information possessed by police; and (2) its degree of reliability.

This standard comes from the 2014 United States Supreme Court case Navarette v. California, in which a civilian driver had called 9-1-1, saying they had just been run off the road by someone who was operating recklessly. Using details provided by the caller, officers located a vehicle of interest and followed it for approximately five minutes.

When the driver they were following failed to do anything reckless, the police stopped him anyway and found 30 pounds of marijuana. The defendant challenged the entire stop, arguing that the police had no basis for pulling him over, but the courts sided with the State every step of the way.

Per the Supreme Court majority, it’s entirely possible for an anonymous tip to demonstrate “sufficient indicia of reliability to provide reasonable suspicion to make [an] investigatory stop.” In other words, as long as the information is sufficiently reliable, traffic stops based on anonymous tips are A-OK.

Was the Anonymous Tip Sufficiently Reliable?

In explaining why it’s acceptable for police to pull people over based on anonymous civilian tips, the majority emphasizes the reasons why it found the 9-1-1 call in this case to be sufficiently reliable. For one thing, it was highly detailed, offering the offending vehicle’s color, make, model, and license plate number.

For another, the timeline of the case suggested that the call was made shortly after the caller had been run off the road, and “[t]hat sort of contemporaneous report has long been treated as especially reliable.” Finally, 9-1-1 calls aren’t strictly anonymous in that the caller can be identified even where they don’t provide their own name.

Because of this (says the majority), we don’t need to worry about the possibility of prank calls, false reports or so-called informants misusing State resources for personal revenge—there are no inherent problems with using an anonymous report from an unidentified civilian source to justify a traffic stop.

Did the Tip Create a Reasonable Suspicion of an Ongoing Crime?

The only other consideration, as far as the Navarette majority is concerned, is whether the information received by police created the reasonable suspicion of an ongoing crime. Reasonable suspicion, in turn, depends on “the factual and practical considerations of everyday life on which reasonable and prudent men, not legal technicians, act.”

After asserting (but not demonstrating) that its own analysis is rooted in practicality and common experience, the majority makes the shockingly dishonest argument that a single reported incident of vehicle mismanagement “bears too great a resemblance to paradigmatic manifestations of drunk driving to be dismissed as an isolated example of recklessness.” In a feeble justification for its position, the majority declares that reasonable suspicion “need not rule out the possibility of innocent conduct.”


As you might have already guessed, Navarette is one of those hotly-contested 5-4 decisions where you need to read the dissent to find out what really happened. There, the minority offers a principled rebuke to the majority’s evisceration of the Fourth Amendment, noting first that its “reliability” reasoning is bogus.

At the time the police were acting on the anonymous tip, they knew absolutely nothing about its source or the accuracy of its details, and therefore could only ever perform a post-hoc reasonability analysis. It also noted that the absence of actual anonymity on 9-1-1 calls is only relevant where the caller is aware of it, which is a point the State had made no effort to prove. The minority likewise took the majority to task for mischaracterizing the substance of the 9-1-1 call as an excited utterance, which is a specific term of art that relates to hearsay evidence and its admissibility.

Apart from the question of reliability, the dissent also disputes the idea that the available evidence suggested the existence of an ongoing crime. Unlike the majority, the minority acknowledges that any number of things might cause a vehicle to swerve unexpectedly. In rejecting the majority’s conclusion, the dissent reasons that “in order to stop the [defendants] the officers here not only had to assume without basis the accuracy of the anonymous accusation, but also had to posit an unlikely reason (drunkenness) for the accused behavior.”

On top of all this, the police had followed the allegedly reckless vehicle for five minutes and had observed nothing but impeccable driving. In other words, at the time officers pulled the driver over, they had absolutely no evidence of ongoing criminal activity—or even of an ongoing danger to the public.

Closing Thoughts

The dissent closes with a warning: “After today’s opinion all of us on the road, and not just drug dealers, are at risk of having our freedom of movement curtailed on suspicion of drunkenness, based upon a phone tip, true or false, of a single instance of careless driving.”

Thanks to the overreach of the Navarette decision, police are now able to presume your intoxication and pull you over based on an anonymous tip. This should worry anyone who’s concerned about the expansion of police powers, and we should draw very little comfort from the fact that this newfound advantage hasn’t been exploited more aggressively by the States.

The attorneys at the Marc Lopez Law Firm defend those accused of intoxicated driving throughout the state of Indiana. If you or a loved one has questions about DUI / OVWI charges, give us a call at 317-632-3642, and remember—always plead the 5th!