One of the murkiest areas in Fourth Amendment law.

A few months ago we published a guide to not getting arrested that was based on the experiences of a long-time police officer-turned-attorney from Miami, Florida. Last on our list of do's and don't's was this piece of advice: Never, ever consent to have your car searched. What we didn't mention in that piece is that the police have a loophole that will allow them to search your car without probable cause, a warrant, or your consent. The loophole's name is Fido. 

But first let's review: The Fourth Amendment of the U.S. Constitution forbids the police from conducting searches and seizures without a warrant or probable cause. In a lot of cases, they get around this by asking you for permission to conduct a search. This puts you, the driver, in a tricky situation, largely because "consensual encounters" with an armed stranger who can arrest you very seldom feel consensual.

Nevertheless, if you're driving a few miles above the speed limit, have a brake light out, or your tag is expired, and a police officer responds by pulling you over and asking to search your car, you have the right to say no, because those things by themselves are not suggestive of a crime.

The police can of course end up having probable cause if say, your car reeks of marijuana (not clear on what counts as probable cause? watch this short video), but if they don't, consenting to a search is setting yourself up for trouble. Maybe your teenager left a joint under the seat, or maybe one magically appeared there as the officer was looking through your car. In either case, say goodbye to your car and hello to a jail cell. And if there's absolutely nothing incriminating in your vehicle, you've still had your privacy violated, your time wasted, and your nerves frayed. Don't volunteer for that. 

But if a cop really wants to search your car without probable cause, a warrant, or your permission, there is a way for them to do that. The U.S. Supreme Court ruled in Illinois v. Caballes that walking a drug-sniffing dog around a car is not an unreasonable search so long as the process is not "unreasonably" long.

"Basically," says the Fourth Amendment advocacy group Flex Your Rights, "if police can’t bring a dog to the scene in the time it takes to run your tags and write a ticket, the use of the dog becomes constitutionally suspect."

This brings us to a murky area in Fourth Amendment law: How long is too long? 15 minutes? Seven minutes? 20 minutes? An hour?

Last Friday, the U.S. Court of Appeals for the Eighth Circuit weighed in on what they think constitutes a not-too-long amount of time. 

Here are the case details: Omaha Police Officer Morgan Struble sees a car "veer slowly onto the shoulder of the highway, before jerk[ing] back onto the road," and pulls the car over. It's 12:06 a.m. Struble is a K9 officer and has his dog in the car with him, but he leaves the dog there while he conducts the stop. The driver of the car tells Struble that he veered off the road to avoid hitting a pothole. Struble goes through some routine traffic-stop stuff, ending with the issuance of a warning to the driver at "at 12:27 or 12:28 a.m."

(KellyNelson /

So, from stop to citation, roughly 21 minutes elapse. At this point, Struble can let the guy go. Instead, he radios for assistance and asks the driver if he can walk his K-9 around the car. The driver declines and Struble instructs him to exit the vehicle. At 12:33 a.m., backup arrives. At 12:34 a.m., Struble walks his canine around the car. On the second pass, the dog signals, giving Struble legal cover to search the car. He finds a bag of meth, and arrests the driver.

Total time from being pulled over to breaking out the K-9? 28 minutes. So the question before the court was whether the elapsed time in this case was longer than the undefined window of reasonable time alluded to by the Supreme Court. The driver of the car petitioned to have the evidence against him suppressed, arguing in his motion that "the stop was unreasonably prolonged by the dog sniff in the absence of reasonable suspicion to continue his detention."

The U.S. Court of Appeals for the Eighth Circuit disagreed. "A brief delay to employ a dog does not unreasonably prolong the stop...and we have repeatedly upheld dog sniffs that were conducted minutes after the traffic stop concluded," the court wrote in its opinion. In the Struble stop, "the resulting seven- or eight-minute delay is similar to the delay that we have found to be reasonable in other circumstances." In other words, the court said the stopwatch starts after the citation is issued, not after the car is pulled over, and that an additional six to seven minutes is a de minimis (or insignificant) intrusion on a driver's privacy, regardless of how long the stop lasted prior to the issuance of the citation. 

To further complicate things, the Nevada Supreme Court gave a very different take on a similar question in July 2013. The backstory in brief: A Nevada Highway Patrolman stops a driver for speeding at 7:10 a.m. on a Sunday morning. Over the course of the next nine minutes, the Nevada trooper collects the driver's information, runs it, asks the driver what he's up to, gives him a ticket, and tells him to have a good day. Then, just as the driver's about to leave, the trooper decides to prolong the interaction with the goal of checking out the guy's car. The guy asks to leave, the trooper says he can't. No reason is given. Eventually a dog arrives, the car is sniffed, drugs are found, and the driver is arrested. 

The second half of the stop lasts from 7:19 a.m. all the way to 8:58 a.m., but the Nevada Supreme Court ruling doesn't even bother assessing whether the post-citation interaction was too long. Instead, the court in this case ruled that at no point during the nine minutes it took for the Nevada trooper to run the tag and issue the citation did the driver give him any reason to prolong the interaction beyond that time frame. 

To tie it all back together: How long can a police officer keep you on the side of the road? The only real answer we have is whether or not that officer's decision is upheld by a court.

If this all sounds rather academic, legal blogger Orin Kerr has a great explanation of why the answer matters: "If courts say that the police can’t extend the stop even one second to bring over the dogs, then the dogs will only be used when they happen to be right there or some reasonable suspicion exists specifically justifying their use," Kerr writes. "On the other hand, if the courts say that the police can extend the stop for a long time, then the police will be free to bring out the dogs at routine traffic stops whenever they like."

It should go without saying that prosecutors should not be the ones determining how long is too long. The prosecutor in the Nevada case, for instance, argued that the driver's detention was “not a very long period out of [his] life." I'm not sure I want a police officer making that determination on my behalf. 

In any event, the best course of action is to always say as little as possible as politely as possible. And always decline a search. 

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