How Do Detection Dogs Find Drugs?

How Do Detection Dogs Find Drugs?

We’ve become so accustomed to seeing it in the news these days, that it could be easy to be desensitized to it. Yet it remains a remarkable fact that K9 teams across the nation can harness the natural ability of exceptional dogs to locate illegal substances. Just take a look at these recent, newsworthy examples:

  • Greensboro residents face drug, weapons charges after traffic stop
    “After speaking with the two passengers, the deputies utilized K-9 Bosco to perform a walk-around of the vehicle. Bosco gave a positive indication to the presence of odor of illegal narcotics inside the vehicle, Campbell said.

    During a search of the vehicle, deputies located 16.2 grams of cocaine, 21.3 grams of crystal methamphetamine, and 10 grams of marijuana.”
  • Virginia man arrested with 300 grams of methamphetamine in Statesville
    “The deputies called in for a canine unit for further investigation. Deputy M. Hicks and his canine arrived, and conducted a walk-around of the vehicle. The canine gave a positive indication for the presence of illegal drugs in the vehicle…a search of the vehicle uncovered more than 300 grams of methamphetamine.”
  • Sheriff: Crystal meth, crack cocaine found; two arrested
    “The two told deputies they were traveling to West Virginia to go to a casino, but inconsistencies in their stories and travel plans, prompted the use of a canine to search the vehicle.

    [K-9] Bosco alerted for the presence of illegal narcotics and a further search uncovered 907 grams of crystal methamphetamine in the driver’s floorboard and 41.2 grams of crack cocaine on Tartt.”

We are privileged to be in a position at Highland Canine to be able to pass on our knowledge and expertise to K9 teams across the United States (and beyond). Removing these harmful substances from our streets plays a vital role in keeping our communities safe.

But have you ever wondered precisely how detection dogs go about finding these substances? In this article, we’ll take a brief look at the history of narcotics detection dogs – and explain how these incredible working dogs are able to locate these substances and make such a difference in communities up and down the land.

narcotics detection searching car

When were narcotics detection dogs first used?

Dogs have been utilized by humans for thousands of years for various jobs, from hunting to herding. More recently, dogs have been used by law enforcement for a number of purposes, including narcotics detection. Narcotics detection dogs were first utilized in the late 1960s and early 1970s, with a focus on improving their training to improve reliability in identifying substances such as heroin, marijuana and cocaine. 

Over the years, as we have started to understand more about how a dog’s nose works – and how odor works – the training methods continue to become more reliable and detection dogs more dependable.

drug detection dog inside school

Explaining how odor works

The first thing to consider when thinking about detection dogs is understanding that they are not trained to locate drugs themselves. They are actually trained to locate the odor of drugs, and usually rewarded with a favorite toy at the source of the odor. To truly understand how the dog is working to locate the odor, we need to take a step back and understand how odor works.

The first thing to know about odor is that it spreads. How fast, and how far, the odor will spread can depend on many things – for example, the quantity of the substance, or the environment in which the odor is present.

Think about it like this – if cookies are put in the oven to bake, it will usually be several minutes before anyone present in the kitchen can smell them. It will take several more minutes before they can be detected in a different room. However, the longer they are baked, the more odors are produced. These odors then have the opportunity to spread throughout the home. 

The cookie analogy also applies to narcotics – or any substance, for that matter. As the odor spreads from the substance, it will seep through any vehicles, bags or barriers. Even objects and containers that are advertised as airtight have microscopic holes and pores that odor will leak out of given enough time. This spreading of odor is the reason dogs are able to locate odor even buried deep inside of vehicles, wrapped in layers of plastic, or deep inside buildings.

drug detection dog in training

Working the scent cloud

The area that the odor is spread to is referred to a scent cloud. Once there is odor produced, a well-trained dog is going to use the scent cloud to get to the source of the odor or where the production of odor is the strongest. Detection dogs do this by figuring out where odor stops or gets weaker, rather than simply following one steady stream of odor. This is because as the scent cloud expands from its source, the odor will move in several different directions. How it moves will vary depending on the environment.

As the dog works the scent cloud, they will oftentimes move quickly back and forth over the source, narrowing down where the odor is coming from. This behavior is called bracketing. Because of the need to work through and eliminate where odor stops or gets weaker, detection dogs often have a harder time locating hides that have been sitting out for a long time. With time and consistent training, dogs become faster at working scent clouds, even with lots of odor to work through.

Using these scent clouds, narcotics detection dogs are able to locate odor anywhere. The scent cloud expanding will push its way through all types of confinements and masking odors, making working dogs the most reliable way to know for certain if narcotics are contained inside of a vehicle, storage area, house or any other area. 

And that – simply – is how detection dogs find drugs!

belgian malinois drug detection dog