No, “Pit Bull” Dogs Don’t Lock Their Jaws, and Other Myth-Busting Facts

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 lay down some facts so that you have a few talking points to share with your community and anyone else who may be misinformed. (We’ve even put all of this information into a printable cheat sheet for you!)

Mowgli – an AFF available dog

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

They Bite Differently, Don’t They?

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).

Source: Animal Farm Foundation

There are a few issues with this – least of all that the media is inconsistent with the biting pressure, with the PSI varying from article to article, and we address this in our BSL ebook – but the main issue is that it’s just not true.

An article in the Journal of Veterinary Dentistry busts this myth wide open. 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.

On top of that, scientists consistently use the unit Newtons to quantify force, not pounds per square inch. Dogs, in general, can have a biting power that ranges from 13 to 1394 Newtons.

Source: Animal Farm Foundation

The above are the most popular misconceptions about the anatomy of dogs labeled “pit bulls,” but there’s a lot of misinformation floating around out there about their behaviors.

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.

Source: Animal Farm Foundation

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.

Here’s what they found:

“[There is] no significant difference in behavior between breeds was detected. The results show no indication of dangerousness in specific breeds.”

Yet again, scientific research proves what we already know – “pit bull” dogs are perfectly normal.

Surely that’s Only Some “pit bull” Dogs, Right? Aren’t Most of Them Aggressive?

Again, science answers with a big nope!

The American Temperament Test shows that the American pit bull terrier, American Staffordshire terrier, and the Staffordshire bull terrier (three purebred dog breeds, typically referred to as “pit bull” dogs), as well as the dogs labeled “mixed breed,” consistently score above the average for all breeds tested, year in and year out. 

Source: Animal Farm Foundation

What does this mean exactly? Well, it means what we say over and over again – every dog is an individual and we should evaluate them as such.

Are You Sure? Aren’t They More Likely To Injure Humans or Other Dogs?

Can you guess what science says about this? Science comes at this with another hard no. 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.


Don’t forget, you can find all of this information in a printable cheat sheet on our website.