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Tueller Drill: The 21-Foot Rule

February 20, 2018 by David Dolbee 2 Comments

The 21-foot rule is thrown around quite a bit, and to be honest, CCW trainers and law enforcement have been rather careless about its use as well—at a minimum, they have not properly explained it to most. Through the use of the word “rule” it makes it sound like a line in the sand or you are magically safe at 22 feet. This has lead to unfortunate conclusions in the world of self-defense and courtroom alike.

Bloody knife on a blood stained white towel
Don’t a victim of bad tactics, based on faulty information.

What Is the 21-Foot Rule?

My first introduction to this topic came about 25 years ago while attending the sheriff’s academy. I remember the class and, more important, the video “Surviving Edged Weapons.” The video and instructional seminars were based on research by Salt Lake City trainer Dennis Tueller. The “21-Foot Rule” was a measure of distance that related to the time it would take an officer to recognize a threat, draw a sidearm, and fire two rounds center mass against an attacker charging with a knife or other stabbing weapon.

To be clear, this article is not intended to be the rule or guide to law enforcement. In fact, most of what this article covers will be common knowledge to today’s LEOs. However, I would hope those with experience behind the badge will chime in and challenge or correct the assertions I scribe here by supplementing it with their own experiences. The ultimate purpose is to give some real-world guidance to the nonprofessional concealed gun handlers reading The Armory.

Examination

The first issue I have with the 21-Foot Rule is the belief that it is somehow rooted in police doctrine or a legal standard. Removing the number “21” and the word “rule” would go a long way toward dispelling the myth. Tueller’s research did not culminate in a rule; you are not suddenly safer at 22 feet than you were at 20. It is important to distinguish that Tueller developed a drill, not a standard.

Just as many firearm enthusiasts insist on the distinction between a modern sporting rifle and an assault rifle, magazine versus a clip, and a dozen other examples we could come up with off the top of our heads, I believe we need to properly identify our subject as the Tueller Drill and not the 21-Foot Rule. This is not only factually true, it goes a long way toward setting the correct mindset of the neophyte gun handler.

21-foot rule meme of a knife wielding attacker
Memes such as this are dangerously deceptive. The 21-foot rule is not a distance of safety, it is a minimum distance in which a person may have a chance to stop an attacker with an edged weapon.

There were two main conclusions that can be contributed to Tueller’s research. First, an attacker with a knife can cover 21 feet in about 1.5 seconds. (This is not word for word, but it covers the general gist.) Second, a helluva lot of law enforcement would be lucky to recognize a threat, unholster their sidearm, and successfully stop the threat from being able to deliver a blow with a knife in less than 1.5 seconds. This was quite a revelation at the time and created much discussion.

Lessons

Tueller’s lesson should not indicate that anyone, even if they have a knife in hand, is a justified bullet sponge. How many of us carry a pocketknife? Every waitress or busboy in a restaurant would have a target on their chest. Not even in the context of a heated confrontation could you immediately jump to this conclusion. The lesson does not teach that we should shoot a hostile actor with a knife if they are within 21 feet. The lesson merely put a number to the test data and created a mindset for officers to rethink their response and posture to a threat or potentially sudden dynamic attack.

The mindset was fine, but the lessons that followed…not so much. Tueller’s research revealed training deficiencies of the day. As previously stated, it created a lot of discussion, which was good. Where it went wrong, in my opinion, was when they started teaching the number over the mindset. I recall this being demonstrated on the range at the academy. A large, intimidating deputy with a rubber knife rushed a student from 21 feet. The deputy did not run, just marched at a quick pace wielding the knife over his head and screaming obscenities.

Police officer next to a red bard with a drawn Glock pistol
Teuller’s drill is well suited to law enforcement and civilians, but the 21-Foot Rule is not.

The student had to recognize the threat’s approach, unsnap his holster, and draw his weapon. He failed. In fact, the truth be told, we all failed. Some may have cleared leather and pulled the trigger, but the threat was so close he still would have struck a blow falling on you. Let’s not forget the audience here. You are likely carrying concealed, not openly in a Sam Brown.

The 21-Foot Lesson was—graphically—received. Unfortunately, at the time, we learned the number more than the correct lesson. In time, however, we learned to get off the “X” instead of being a static target. Instead of backing up in a straight line, we were taught to react by moving “off-line.” (Attackers in these scenarios may be so enraged they continue on the beeline path instead of tracking you.) More important, we were taught to read body language, situational awareness (which directions could you move off-line, soft and hard cover, etc.), reactionary gaps, and other close-quarters defensive techniques not involving a firearm.

Final Thoughts

The focus of The Armory does not include training civilians to be cops or instruction in matters of law enforcement. However, I see far too many videos of self-professed firearm trainers, tactical weapons specialists, home defense “experts,” and even a few prior LEOs who teach concealed carry like they did to officers or cadets at the academy or in the military and not to civilians. Sadly, I would say while I respect the effort, they have no business standing in front of a student. Too often, I have heard friends (after such training, watching a cop show on TV, or reading something on the Internet) throw out the term “21-Foot Rule” and improperly state it as a threshold of safe versus justifiable homicide.

I hope, after reading this and the comments from readers with much more knowledge and experience than I have, that you dedicate some of your concealed carry training to going beyond the minimum gun-handling skills and—as important—practicing your communication skills, situational awareness, and good old-fashioned common sense.

What is your impression of the 21-Foot Rule? Have you ever heard of the Tueller Drill? Have you practiced it? Share your answers, opinions, or experiences in the comment section.


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Filed Under: Self Defense Tagged With: 21-Foot Rule, Concealed Carry, Self-Defense, Tueller Drill

Reader Interactions

Comments

  1. Ralph Carter says

    February 23, 2018 at 4:18 pm

    LEO’s, federal, state, county, and city, are civilians. Non-LEO’s are appropriately termed citizens.
    Check the Posse Comitatus act.

    Reply
  2. D Payne says

    February 23, 2018 at 6:07 pm

    I learned a lesson from a fast-draw cowboy working on a supermarket grand opening when I was a new policeman. He told me I could draw my gun, hold it aimed at him and he could draw and shoot me before I could shoot him. Since I was new, I didn’t believe him. He had me unload my weapon, his was unloaded as well. I held my gun on him, had my finger on the trigger, pressing against it. He drew his single action cowboy gun and clicked off a shot before I could fire at him. We did this routine several times. He then explained some of the basic facts of human reaction time. He was cocking the hammer back on his gun and sliding his finger into the trigger guard while the gun was still in his holster. As soon as the gun cleared the leather, it snapped off.
    I believed everything he told me. I practiced that trick until I could do it well enough to be able to win a dollar off most every guy in the PD, until they all knew the trick.
    I reviewed my practice of holding prisoners at gun point and always stood further back from them, out of range of long arms with more than one step away. I believe every word in the Tueller Drill. His suggestion of 21 feet seems to me to be a good starting point.

    Reply

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