A Fruitless Motorhome Search Based on an Invisible Dog Alert, Followed by a Puzzling Chase


U.S. Border Patrol

When a vehicle search based on an alert by a drug-sniffing dog fails to discover anything illegal, police typically say the animal must have smelled traces left by contraband that was recently present. As I noted in my March Reason cover story about police dogs, this is a very handy excuse because it is impossible to disprove, especially since there is no firm answer to the question of how long residual odors remain strong enough to be detected. In practice, an alert to residual odor is indistinguishable from a mistake. Another complication in attempting to explain fruitless car searches justified by a dog's alert is that, unless there are witnesses or a video record of the encounter, the only basis for concluding that the dog did in fact alert is that his handler claims he did. Relying on the word of an officer who may want to search a car for other reasons, based on suspicions that fall short of probable cause, poses obvious hazards. A recent search at a Border Patrol checkpoint in New Mexico illustrates both of these problems.

Around 9:30 a.m. on February 20, Dale (who asked me not to use his last name) was driving his motorhome west on Interstate 10 near Deming, heading home to California, when he was stopped at a permanent Border Patrol checkpoint. (The Supreme Court has upheld suspicionless stops at such checkpoints, which can be as far as 100 miles from an actual border, based mainly on the need to enforce immigration laws.) A Border Patrol agent walked a German shepherd around the motorhome, the sort of inspection the Supreme Court has said law enforcement officers may conduct at will during any legal traffic stop. Dale has cameras mounted inside and outside the motorhome (as a precaution against both theft and police harassment, he says), so he has video showing most of what happened during the stop. Although the video does not show the dog during the entire circuit around the vehicle, Dale says he watched the whole thing, via the motorhome's mirrors, except for a moment when the dog was in a blind spot. He says the dog was "not making any indication to [the vehicle] by barking, scratching, or sitting and staring at any particular area." The dog's handler nevertheless signaled his colleagues with a V sign, apparently indicating that the animal had alerted. At that point Dale was instructed to pull into a secondary inspection area for a search. 

Dale and his passenger parked and, following an agent's instructions, exited the motorhome. Oddly, Dale's companion says an agent told him the dog had indicated the presence of marijuana specifically, although drug-sniffing dogs generally are trained to detect several different substances, and they alert the same way to all of them. One of Dale's cameras shows that the dog entered the motorhome with its handler, wandering around for a minute or two but not showing special interest in anything. Then the handler and two other agents searched the motorhome for eight more minutes, at one point chuckling over something they picked up and at another point lifting a bed to look underneath. (Dale says they damaged the bed frame.) Although the dog supposedly alerted to the exterior of the motorhome, the agents did not search any of the compartments on the outside of the vehice. Finding nothing illegal, they sent Dale and his passenger on their way about 15 minutes after stopping them. But it turned out the Border Patrol was not through with Dale yet. A minute or so after he left the checkpoint, two agents chased him in a Border Patrol car with flashing lights and pulled him over. One of the agents had left a metal eyeglass case in the motorhome, which he retrieved, saying (according to Dale), "You do not want to be caught with this in your vehicle!" Dale found the remark (and the chase, which was not justified by anything he had done) unnerving, wondering what the hell was in that eyeglass case.

A Border Patrol spokesman, Douglas Mosier, says it was eyeglasses. "The reason for the subsequent vehicle stop," he explains, "was that the Border Patrol Agent that was assisting in the search of the vehicle inadvertently left his prescription glasses in the vehicle, and they merely sought to recover them." As for why a drug-detecting dog would alert to a vehicle that does not in fact contain drugs, Mosier gives the standard reponse: "Because of their keen sense of smell, canines are able to detect the odors long after the substance has been removed from an area." How long exactly? The question is especially relevant in this case because Dale's passenger, who has a California doctor's recommendation for medical marijuana to treat disease-related loss of appetite, says he had smoked cannabis in the motor home five days earlier. Dale's companion says one of the Border Patrol agents told him the window for detecting marijuana smoke residue is three days. Lawrence Myers, an expert on drug-sniffing dogs at Auburn University, says it is "plausible" that a dog could detect traces after five days, although "it would depend upon a lot of factors," and such a capability has never been scientifically verified. 

So assuming the dog alerted, it might have been reacting to traces of marijuana smoked five days earlier. There is no way to say for sure. But how do we know the dog did in fact alert? Dale says he did not see anything that looked like a signal. When I ask Mosier what a Border Patrol dog does when it alerts, he says, "The manner in which a canine alerts varies from canine to canine." Can he describe the various kinds of alerts? No, he says, "because it is law-enforcement sensitive." I am not sure what that means, but in any criminal case involving a dog-triggered search, the handler is expected to explain how the animal signals. It's not supposed to be a secret. Myers says the Border Patrol's refusal to say what an alert looks like "makes no sense whatsoever." This caginess reinforces the suspicion that agents use dogs as props to justify searches they want to conduct for other reasons. Even in cases where a dog clearly alerts, it may be reacting to its handler's suspicions rather than the smell of drugs.

The free rein that the Supreme Court has given cops with dogs to search vehicles is disturbing enough when police use it to peruse people's cars. It is even more troubling when the vehicle is a motorhome, which contains the same sort of sensitive and potentially embarrassing items that might be found in a residence. Last month the Court ruled that police need probable cause to deploy a drug-sniffing dog at the doorstep of a home. But when the home is on wheels, a canine inspection of the exterior no longer counts as a search. It can be conducted on a whim and, depending on how the dog reacts (or is said to react), used to justify a search of this intimate space without any need for court approval.

Addendum: You can watch an edited video of the stop, narrated by Dale, here and below. He has video and audio of the search here.

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    1. How DARE you misspell on the internet!


      2. Hmm, I thought a HEReo was a threesome between 2 black chicks and a white chick…

        1. Link, please.

  2. Regarding the picture, why do cops need long rifles? Besides the obvious (they are scary and cool). Most of what they do is face-to-face interaction, and if violence erupts a pistol is fine for that situation. Easier to use honestly.

    1. As a firearms instructor, … handguns are a compromise. We carry them because carrying a rifle is inconvenient. Rifles are in most cases a superior choice. Most cop shootings are close encounter oh shit immediate reaction type, but many others – a rifle would be a superior choice. The rifle has better stopping power and accuracy.

      Fwiw, it’s hard to tell from the picture, but that might be a shotgun. The barrel looks big enough.

      1. To take it a step further, I read a lot of shooting reviews. I’ve read several where the perp was still standing and engagin after taking SIX handgun rounds. That is rarely the case with a rifle. The stopping power alone is much much better (huge temporary cavity)

        1. So cops need them because they are more lethal? That sounds like a fine rationale in a war setting, but PEACE officers? Why not a taser or something less-lethal but equally incapacitating?

          1. Why not no guns; peace officers do not need them.

          2. Because it’s too difficult to taze a dog.

          3. The rifles have better stopping power. Handguns are a compromise.

        2. That sounds like bullshit – I have difficulty believing that a 5.56 mm round, even at close range, leaves a larger wound channel than even a 9 mm pistol round.

          1. Again – TEMPORARY cavity. The temporary cavity is much larger and causes immense damage. Look at the work of the Jello Junkies and the wound stuff they have done with shooting pig carcasses.

    2. The same reasons you can’t own them.

        1. Should have said: ” Same reasons politicians don’t want you to own them”.

  3. Around 9:30 a.m. on February 20, Dale (who asked me not to use his last name)

    Last name is probably Episiarch.

  4. Of course under federal law, marijuana is illegal PERIOD, so this stuff doesn’t apply, but…

    The nice thing about legalization of MJ on the state level is that dog alerts are no longer PC to search (in my state, even with PC, you still need a warrant btw. We don’t accept the Carroll doctrine or other exceptions to a warrant requirement for motor vehicles. Yeah WA!) since MJ is legal and dogs that have been trained to detect MJ amongst other drugs are thus useless for developing PC.

    The border exception is over 100 yrs old and well established, but allowing it ONE HUNDRED MILES from the border is a fucking joke. It essentially turns a huge swath of our country into a 4th amendment excepted border zone, which imo was NOT the founder’s intention.

    Border searches should be limited THE BORDER with maybe a 5 mile buffer, but 100 miles? Ridiculous

    1. So, are new drug dogs in WA being trained to detect other drugs but not marijuana now?

    2. “Of course under federal law, marijuana is illegal PERIOD,”
      Except those people permitted by federal law to use and possess marijuana.

  5. “…Dale’s passenger, who has a California doctor’s recommendation for medical marijuana to treat HIV-related loss of appetite, says he had smoked cannabis in the motor home five days earlier.”

    That is as far as I got, and where the article lost me.

    Granted, medical marijuana is legal under state law, but these were not state cops. The dog did or did not alert. There were no drugs present, but there could be residue. Maybe the dog can smell it, maybe he cant.
    By smoking in the motor home they kinda killed their credibility, and gave the cops an edge. DONT SMOKE POT IN YOUR HOUSE OR YOUR CAR. Dont put that shit in your pocket. Dont put it in your car. Dont put it in your house. If you do, this is the kind of bullshit you can expect.

    Having said that, I will state that I am vehemently opposed to prohibition and to the massive fucking that govt. has given to the fourth amendment. All of these laws are abominations and, in my opinion, the government is acting illegally.

    Yet those laws are there so dont give them an excuse. Lets change the fucking laws.

    1. We’re working on it. Two states already. Again, makes no difference with the feds, but on the local level, a dog alert is now useless here because MJ is legal, thus a dog alert doesn’t necessarily indicate contraband.

    2. By smoking in the motor home they kinda killed their credibility, and gave the cops an edge.

      I agree.

      Not an ‘edge’ as in a moral correctness, but an edge in that, “well, ok, federal officers are looking for federal contraband, and the passengers are admitting that federal contraband had been within the vehicle in the last five days”.

      I have come to absolutely loathe the concept of bomb drug sniffing dogs, but it seems reasonable to me that a well trained dog could smell contraband that had been in an area within the last say, three to seven days.

      Hell, I saw a documentary on just how sensitive a dogs nose is– something like the ability to detect 1 scent molecule at 9,000 yards.

      Did the dog alert?

      Probably not.

      Are the BP agents corrupt motherfuckers?

      Most definitely.

      What was in the ‘eyeglass case’?



      So, don’t smoke pot? A house is usually the most private place a person has. A car secondarily, depending on the type of vehicle, tinting etc. Most people who are arrested for possession are probably smoking somewhere that their activity is visible. Sometimes I pass dudes at bus stops who are smoking was clearly smells like reefer, and I’m baffled they are putting it out there like that. It’s like they’re begging for an off-duty cop or something to bust them.

      1. I know a guy like that. He’s always posting pics of weed he got on FB and he’ll walk around DC with a blunt lit. He thinks it’s OK because he has a prescription. He’s not real bright.

        1. What is his IQ?

  6. The free rein that the Supreme Court has given cops with dogs…


  7. Dale, quit messing with Texas.

  8. Oh, fwiw, I have never heard of a dog giving a SPECIFIC alert for MJ as Dale was told by the BP agent in this example. That’s not to say it’s not possible; there may be dogs who have been trained this way, but I’ve worked with drug dogs frequently and I’ve never heard of such a thing. It makes me go hmm… Iow, I’m not calling bullshit outright, but I’ve never heard of it before and it makes me suspicious it’s bullshit

    1. I have no problem calling bullshit.

      I have seen cops lie their asses off a thousand times and laugh about it later. Some poor schmuck gets his life crushed over a fucking seed and they laugh about that too.

      I am not saying all cops are like that, but there is a high percentage who are.

    2. Oh, and Dunphy, if something makes you suspicious that it is bullshit, it is a safe bet to put it in the bullshit column until it proves otherwise.

      1. This. The burden of proof lies with the police. How did the dog signal specifically? Did it wag it’s tail a certain way? Ask for a scooby snack? Seriously, wtf is the rationale?

        Oh wait. It’s “law-enforcement sensitive”. Guess we just have to lick the boot and accept it.

      2. I’m not in the kneejerk jump to conclusion with minimal evidence camp like most people here. Like I said, it makes me suspicious. I’ll leave it at that. I readily admit I am far from an expert on dog alert stuff, although I have quarried with drug dogs and certainly know more about how they operate than most people.

        IME, they do not have particularized alerts for MJ vs. other drugs. But it MAY be the case that certain dogs do. It could also be the case that this border agent lied to dale. It could also be the case that dale misunderstood the BP agent. All sorts of POSSIBILITIES but without further evidence, I am not going stampeding towards the clitoris and making unfounded assumptions. It makes me go hmmm… and I leave it at that, at this point.

  9. I’m waiting to read the article where the Snoop Dog tour bus gets busted on I-10.

    1. I’d bet that they plan carefully to avoid permanent border checkpoints.

      1. I’d pay money to see the Snoop Dogg tour bus drive overland through the Deming area.

    2. Not sure if Snoop’s been busted, but I’ve heard of several other musician’s tour buses getting busted. They probably avoid using I-10 now or going anywhere within 100 miles of a border.

      1. Didn’t… Fiona Apple’s(?!!) bus get busted somewhere?

        1. Every tour bus gets swept going through Texas. Bands should completely boycott and bypass the fucking place.

          1. So much for freedom of travel.

    3. Pretty sure he’s Snoop Lion now.

  10. No, he says, “because it is law-enforcement sensitive.”

    That’s Law-enforcement-ese for “go away, reporter”

  11. “chuckling over something they picked up”

    gallows humor they need to entertain themselves w/ something while they do their jobs nothing rong w/ this imo


    1. Yup, mocking people over what you find when you are uninvited in their home is perfectly fine and totally unremarkable. For conscienceless assholes.

  12. 1. Are the dogs trained to detect illegal aliens? No? Then why the fuck are they being used at a checkpoint specifically authorized to check for illegal aliens?
    2. If there are people in the US that are legally allowed to use and possess marijuana, then a drug-dog alerting to marijuana is NOT probable cause to initiate further search.

    Waiting for Dunphy to chime in so I can tell him where he’s wrong…

    1. Fuck, these guys enforce *DUI* laws, which are state only, and DHS and eve Game and Fish types have been known to pull over speeders which is technically not even a crime (depending on how far over the limit you were).

      1. There are federal DUI laws. Heck, I’ve patrolled with the coast guard who enforce DUI on our waterways.

        DUI on federal property is enforced by federal law, but it is true that on the freeway, DUI enforcement is limited to local (state) law.

        I would assume if a border officer stops a guy he suspects of DUI, that he would detain him and call the local cops (state patrol etc.) to do the investigation.

        This is similar to what we do when we stop somebody and we detect what we believe is a violation of federal law. We call the feds.

        Also, sometimes border agents are sworn in as “special” police in the area they work so such detentions are more legally justifiable. But either way, a federal officer can detain somebody he suspects of DUI and call local police to conduct the investigation.

    2. “1. Are the dogs trained to detect illegal aliens? No? Then why the fuck are they being used at a checkpoint specifically authorized to check for illegal aliens?”

      Border checkpoints are not purposed for, or limited to- checks for illegal aliens.

      Checks for contraband crossing our border are part of the reason we have border checkpoint s in the first place. You are operating under a false premise – that border checkpoints are only supposed to be for the purpose of searching for illegal aliens. Searching for contraband (and not just drug contraband) is a major reason we have border checkpoints.

      “2. If there are people in the US that are legally allowed to use and possess marijuana, then a drug-dog alerting to marijuana is NOT probable cause to initiate further search”

      unfortunately, at the federal level such “legally possessed” marijuana is not recognized as valid. Iow, the feds don’t recognize the legitimacy of medical marijuana (or legalized marijuana in general).

      What you are saying *is* true on the staste level, but unfortunately as far as the feds are concerned, MJ is still a schedule I controlled substance.

      I don’t understand the hostility here. You may be ignorant on these points, but we both agree that 100 mile border checkpoints are bad, the WOD is bad, etc. So stop trying to make an argument when there is no argument and stand corrected on these points that I schooled you on. You’re welcome

      1. Checks for contraband crossing our border are part of the reason we have border checkpoint s in the first place.

        Driving across the state of New Mexico is not crossing an international border genius. Neither is crossing from AZ to CA.

  13. “Because of their keen sense of smell, canines are able to detect the odors long after the substance has been removed from an area.”

    True, I do not have a canine olfactory, but daaaaamn that smells like bullshit to me.

    law-enforcement sensitive

    Funny, but my bullshit detector is sensitive too.

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