No, “Pit Bull” Dogs Don’t Lock Their Jaws and Other Mythbusters


October, 2019

There’s a lot of misinformation out there regarding “pit bull” dogs. It’s so prevalent that you might actually believe some of the myths, even if you are a lover of dogs often labeled as “pit bull” dogs.

We thought we’d drop some knowledge so that you have a few talking points to share with your community and anyone else who may be misinformed.

Let’s get started busting some myths, shall we?


On of the most popular misconceptions about “pit bull” dogs is that they, unlike other dogs, lock their jaws.

Here’s the reality: According to Dr. I. Lehr Brisbin of the University of Georgia, no dog, of any breed or mix, has an anatomical structure in their jaw that functions as a locking mechanism.

Dr. Brisbin said:

“We found that the American pit bull terriers did not have any unique mechanism that would allow these dogs to lock their jaws. There were no mechanical or morphological differences. . .”

Okay, but what about their biting power?

The media and other outlets often say that “pit bull” dogs have a massive biting power measuring in the thousands of pounds of pressure per square inch (PSI).

There are a few issues with this – least of all that the bite pressure varies from article to article,  but the main issue is that it’s just not true. 

And the simplest way to bust this myth wide open is researchers consistently use the unit Newtons to quantify force, not pounds per square inch. Any claims about “pit bull” dogs and PSI have no scientific backing whatsoever.

According to what we currently know, no dog is biologically equipped with a unique biting mechanism or style that would differentiate them from other breeds of dogs. There is zero scientific research that substantiates this claim.

Don’t they attack without warning?

This is another doozy of a myth. Like we already established in regards to their bite strength and jaws, “pit bull” dogs are just like any other dog. The same applies to their personalities.

All dogs, including dogs commonly labeled “pit bull” dogs, signal their intent. The Institute of Animal Welfare and Behavior of the University of Veterinary Medicine in Hannover, Germany did temperament tests on over 1,000 dogs.

The results indicated that breed did not dictate an individual dog’s behavior.


Can you guess what research shows about this?

There is no scientific evidence that one kind of dog is more likely than another to injure a human being or another dog.

The American Veterinary Medical Association says:

“Controlled studies have not identified this breed group [pit bull-type dogs] as disproportionately dangerous.”

There are three big takeaways here.

One: Dogs labeled “pit bull” dogs are just like any other dog.

Two: When in doubt, consult scientific research.

Three: All dogs are individuals.

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