K-9 Units and Military Working Dogs

Every year on March 13th, K-9 Veterans Day is observed across the U.S to reflect on the elite dogs that served our citizens and country. In honor of this holiday, we will be utilizing this blog to bring awareness to both K-9s and military working dogs.

K-9s (short for canines) and military working dogs (MWDs) execute essential roles in various military branches and other law enforcement capacities, but not many people realize the scope of their duties and skills or consider the differences. Below we will discuss a brief history of these two types of enforcement dogs, how they are currently utilized in America, and the variety of duties they perform while on the job. 

Brief History of Police and U.S. Military Dogs:

The Department of Defense’s website highlights a short history of military working dogs that goes into more detail than we will cover here, so we recommend visiting their site if you care to look more in-depth. There is evidence of dogs being used in times of war as far back as 600 BC by the Romans, Greeks, and Egyptians! In more recent times, the roles that dogs carry out for the U.S. military have slowly grown more complex.

While they were originally just used to carry gear packs in the Revolutionary War, they had the unique job of killing rats in the trenches at Normandy during WWI. After their roles in those two wars, Americans began to realize the value that specifically trained military dogs could bring to the front lines.

In World War II, the U.S. deployed more than 10,000 trained canines, most of whom were sentry dogs, but others were trained as scouts, messengers, and mine detection dogs. Recent data suggests that there are currently roughly 3,000 military working dogs deployed both nationally and internationally in U.S.

Customs and Border Patrol, military, federal law enforcement, and police K-9 units. Police K-9 programs began in London and other European cities post World War I, but surprisingly, the use of police dogs didn’t take off in the U.S. until the 1970s. Now, K-9s are highly valued and widely used by both local and federal law enforcement agencies countrywide in the United States.

Police K-9 Units:

Origination and Preferred Breeds:

Most police dogs are bred and trained in Europe and are typically shipped to the U.S. from there, which can cost upwards of $8,000. Many people think that police officers teach their K-9s attack commands in a different language so that nobody other than the handler can cue the dogs, but this is a myth!

These European dogs learn the training commands in their native language, typically Dutch or German. So, instead of completely retraining the dogs using English words, which would be time-consuming and confusing to the dogs, their new handlers just learn to use the commands in the dog’s native language. 

The majority of U.S. police K-9s are German shepherds, although Belgian Malinois and Labrador Retrievers, as well as a few other breeds, are used as well. These breeds are specifically chosen for this type of work because they are aggressive, intelligent, loyal, athletic, and have an excellent sense of smell.


Only very dedicated officers work with the K-9 unit as it is a very demanding job to take on. A K-9 officer typically works 60 hours per week and must commit to working with that department for at least six years, which is the average length of a K-9 dog’s career. Once assigned to a specific police officer, each K-9 dog lives with their unit partner. This means the K-9 unit is a team that stays together 24 hours a day, seven days a week. Once these police dogs go into retirement, they typically live out the rest of their lives as family pets with their handler.

K-9 Jobs:

  • Attack: Canines are naturally both faster and stronger than most humans. So, on the job, K-9s are specifically trained to apprehend fleeing or aggressive subjects by clamping down on them with their powerful jaws until other officers arrive and are able to take control of the situation. In some circumstances, they are deployed because they are able to catch suspects quicker and more efficiently than the officers. However, usually, the intimidating presence and growl of police K-9s are enough to convince suspects to surrender instead of running or fighting. This helps to quickly de-escalate situations out in the field. Suspects also understand that they cannot intimidate or reason with the K-9, which helps keep officers and citizens out of harm’s way by preventing physical confrontations. 
  • Drug/Explosives/Weapons Detection: Although police dogs are used for apprehending suspects, they are primarily utilized as detectors in the field. Their sense of smell is about 50 times more sensitive than a human’s, which makes them incredibly efficient at executing detection work. In turn, their remarkable sense of smell makes it difficult for drug or weapon smugglers to mask the scents of their paraphernalia. Impressively, a dog can discern specific scents even when those aromas are masked with dozens of other surrounding smells. To put it in perspective, dogs can detect smells in parts per trillion. An example highlighted in an article by The Blissful Dog, dogs can detect “one rotten apple in two million barrels, which is about 752,000,000 apples.” Here, you can find some other fascinating facts and real-life examples of how impressive a dog’s sense of smell is. 


Common questions regarding K-9s are how do they learn to detect different drugs or weapons when on the job, and how young do they start learning? The youngest age these dogs typically start their training is between 12 and 15 months of age as this is when they are mature enough to concentrate effectively. 

They start with basic obedience training and then move into learning other specific skills such as agility, tracking, and detection. To begin tracking/detection training, generally, the handler introduces the dog to a game of tug-of-war with a scentless white towel and just simply plays with the dog.

Later, the drug or weapon the dog needs to be able to detect in the field is rolled up inside the same towel so that it takes on the scent of that object. The dogs start to associate those smells with their favorite toy and game: towel tug-of-war. The handlers then begin hiding the towel with the drug’s scent or (unarmed) weapon wrapped in it for the dog to search out in various places and environments.

When the dog finds the hidden drug/weapon towel, they are immediately rewarded by playing tug-of-war with the towel. Soon, the dogs learn that if they sniff out those aromas accurately, they get to play and are motivated by that. As training progresses, various scents are introduced and learned by the dogs using this same technique until they are able to detect any and all substances or objects they will need to know for their job.

The same method is used for bomb-detection dogs, except various chemicals used to manufacture explosives are placed in the towel instead of drugs or weapons. Detection dogs learn to discern upwards of 19,000 different scents for their job!

Most police dogs not only learn how and when to attack an assailant and detect drugs, but they are also cross-trained to track people. They learn to “grab” a person’s scent from the ground and track their “scent cone” in the air, which is simply the scent of the person that flows downwind from them when he or she is nearby.

Being able to track scents traveling in the air is important because this allows the dog to perceive if suspect circles back to ambush officers. They can then alert the officer’s way before they might figure out the suspect’s movements themselves, and ultimately these dogs can save lives. Once the dogs are actively using their skills on the job, they will continue to spend approximately eight hours training either weekly or bi-weekly to ensure they stay sharp. 

Military Working Dogs:

Origination and Preferred Breeds:

There are certainly similarities between where police K-9s and military dogs come from and what the preferred breeds are for both roles. However, there are a few interesting differences that are worth noting. Just like dogs used for K9 Units within law enforcement, the majority of MWDs in the U.S. also come from Eastern Europe (Germany and the Netherlands to be precise.)

When fully trained, these dogs can cost upwards of $150,000, which is quite significantly higher than the cost of trained K-9s. In recent years, the American Kennel Club was requested to help create and implement a detection dog breeding program within the U.S. to curb our reliance on European breeding programs. Their aim is to bring down costs and have a solid pool of dogs to pull from stateside.

The breeds used for MWDs are very similar to those used as police K-9s and include the German Shepherd, Dutch Shepherd, Belgian Malinois, and various Retrievers. German Shepherds are the preferred choice due to their consistent desirable traits for the job requirements: loyalty, naturally aggressive, highly intelligent, and adaptability to a multitude of environments.

One exception on breed preference is for the Navy Seals, who mostly use the Belgian Malinois because they have a more compact body build and are small enough to tandem parachute and repel with their handlers while working in the field.


The average career length for MWDs is 8-9 years long. Shockingly, military dogs used to be considered “nonessential surplus equipment” by the military and were either abandoned after service or euthanized once their duties were completed.

However, in the year 2000, U.S. legislation known as Robby’s Law was passed, which made retired or dismissed military working dogs available to be adopted by their handlers to live out the rest of their lives like a house pet.

Those who aren’t adopted by their handlers have the opportunity to either go work for local law enforcement agencies, or be adopted by other veterans through different programs, such as Mission K9 Rescue, and Save a Vet. If an MWD is killed in combat, their squadron honors them by symbolically placing their bowls upside down and reading aloud a poem called, “Guardians of the Night.” 

MWDs Jobs:

  • Sentry Dogs: Sentry dogs are trained to warn their handlers of the approach or presence of strangers and are utilized for guarding supply dumps, airports, war plants, bases, and other vital installations. Over 9,000 dogs trained in this task were used in World War II.
  • Scout or Patrol Dogs: These dogs are trained to work in absolute silence to detect snipers, ambushes, and other enemy forces nearby. Dogs trained in these skills have to be very intelligent and have a quiet and calm disposition. They are also excellent trackers.
  • Messenger Dogs: These dogs learn to work off-leash and have to be equally loyal to two handlers and be motivated to leave one handler to travel to the other and vice versa in order to transport and deliver messages across distances. It is difficult to find dogs that will be equally loyal to two different handlers, as they bond so strongly to one most often. So dogs that can bond to two handlers are good specimens for this type of work. They also learn to move in silence and hide within their surroundings to keep themselves safe as they travel along their routes.
  • Mine Dogs: These dogs are trained to find trip wires, booby traps, and both metallic and nonmetallic mines. In the past, they had some difficulty performing in live combat scenarios, and often dogs that perform these tasks do develop PTSD. Dogs that learn to detect mines are really only utilized within the U.S. Army program nowadays.
  • Casualty Dogs: These dogs are tasked with locating both live and deceased bodies of downed comrades in obscure or hard to reach places that their fellow soldiers probably can’t reach or won’t be able to discover. These dogs have helped save the lives of multitudes of soldiers by finding them in enough time to get them the medical aid needed to survive and continue to do so on duty today. Approximately 300 dogs trained in this style of search and rescue helped recover people caught under debris from the 9/11 attacks on the World Trade Center and were true heroes.
  • Tunnel Dogs: These dogs were taught the specialty task of detecting and exploring the Cu Chi tunnels that were created and used by the Viet Cong during the Vietnam War. This isn’t really a skill that is taught in modern-day military working dog training programs, as it isn’t highly applicable, but they helped the U.S. efforts greatly during the Vietnam War.
  • Explosive Detection Dogs: These dogs are currently used by all branches of the U.S. military and are trained to alert when they detect the scent of chemicals used in explosives. They can sense the explosive chemicals whether they are hidden on a person’s body, inside a vehicle, or in a hidden hole underground. As an enemy, it is extremely difficult to mask the smell of explosives for these dogs since their sense of smell is so superior. The Pentagon actually attempted to create a machine between 2004 and 2010 that would replicate the abilities of bomb-sniffing dogs, but they eventually decided to forgo their efforts because the machines only had an average 50% detection accuracy rate compared to the 98% average accuracy rate of the trained dogs. Their abilities simply just aren’t able to be replicated.


Military working dogs begin their training in Texas at the Department of Defense Military Working Dogs Training School (DoD MWD), which is located at Lackland Air Force Base in San Antonio. At the base, they operate with a staff of about 125 people who have varying experiences from multiple branches of the military.

They train up to 1,000 dogs at any given time, but only 50% of those who enter training will graduate the program. There is actually a specific program here that starts grooming puppies as young as 6 months of age for military fieldwork.

Many puppies are weeded out of the military work track at this stage due to showing signs of distress when they have to bite humans, one behavior that they will eventually be required to perform should they be chosen to become an MWD.

The dogs that do make it through the basic training program and who are bound for detection work, are taught using similar techniques that are used with the police K-9s discussed earlier.

However, instead of using a towel to train with, they may use other items such as a ball or toy kong to better represent the bomb or other items they will be found while on the job. A different research and development sector has recently been created at this base to study better body armor and gas masks for these dogs to use for protection while working out in the field.

K-9s and military working dogs hold a special place in the hearts of those who serve alongside them, as they work tirelessly to protect their fellow soldiers, police officers, citizens, and their country.

If you’d like to visit a war dog memorial to pay tribute to some amazing dogs someday, there are a handful you can access across the country. The Military War Dog National Monument is conveniently located at the Joint Base San Antonio – Lackland and is probably the closest one to Dallas. This article lists other memorials located all across the country that you could visit as well. We hope that this has been an informative blog and that you have a newfound appreciation and respect for both police K-9s and MWDs, as well as for the people that work tirelessly to train them, and those that dedicate their lives to working alongside them. 


  1. https://www.nationalpolicedogfoundation.org/faq
  2. https://people.howstuffworks.com/police-dog.htm
  3. https://www.dogster.com/lifestyle/dogs-sense-of-smell-facts
  4. https://theblissfuldog.com/pages/how-your-dogs-nose-works
  5. https://www.thebalancecareers.com/military-working-dogs-3354121
  6. https://militarybenefits.info/k9-veterans-day/
  7. https://www.akc.org/expert-advice/news/what-are-military-working-dogs/
  8. https://www.dogingtonpost.com/remembering-the-hero-dogs-of-911/
  9. https://www.bringfido.com/blog/war-dog-memorials-to-visit-on-veterans-day/

Credit: Robin Laclede