Self-Defence Against Knife Attacks: Evidence-Based ApproachHarper March 20, 2019 0 COMMENTS
We’ll all agree that in order to adopt realistic methods of defence against knife attacks, we first need to understand how an attacker is most likely going to use the weapon.
But how do we get that understanding?
The truth is, we mostly rely on other people (the ‘experts’) to give us the answers.
The problem is that the Martial Arts / Self-Defence industry is plagued by misconceptions and fallacies.
That’s why I decided to properly research on this topic. I wanted to understand the dynamics of real knife attacks and I wanted it to be based on evidence.Luckily, in recent years CCTV and phone footages have provided us with abundance of real-life examples we can learn from.
Data were readily available for anyone who was willing to carry out the (tedious) analysis.
And today I’m going to share with you the results of my investigation where some interesting findings were uncovered.
This article is structured in three parts:
- Part 1 presents the keys points of the analysis of 150+ knife attacks (video material)
- Part 2 (“How to survive a knife attack”) addresses commonly-debated issues such as awareness, avoidance (“running away”), compliance, the use of weapons (incl. improvised weapons) in the context of knife attacks
- Part 3 (“Bare Hand Techniques vs Knife”) covers a variety empty-hand techniques, from different schools of thought, in view of what’s discussed in the first two sections
*This a substantial article which took months of painstaking and meticulous work, so I hope you’ll enjoy reading it .
**No, I’m not trying to sell anything here (no book, no DVD, no online course). It’s just a research article made freely available to anyone interested in this topic.
KNIFE ATTACKS: FANTASY AND REALITY
Defence against knife attacks remains one of the most contentious parts of Martial Arts and Reality Based Self-Defence (RBSD).
The reason for this, in my view, is that very few people actually have any substantial experience of this type of violence. And among those who have that experience, even fewer are actually keen to talk about it.
So we’re left with people who have been “twice attacked” by a knife-wielding nutcase. Although, I’ll listen to these people -any experience is worth hearing- two incidents don’t make you an expert on a question.
Think about it.
Would a major car-maker hire you as a car-safety expert if you just added “Have been twice in a car crash” to your CV/resume?
It takes more than that.
The issue of expertise, with regard to Martial Arts, was addressed in a very discerning way by Wim Demeere in his 2014 article “Are you really an expert?”.
In the Martial Arts / Self-Defence industry, unfortunately, we too often hear “appeals to self-authority” where the speaker expect you to believe him/her based uniquely on his (often unverifiable) pedigree.
In other words, “Trust me, I’m the expert!”
What is sorely lacking is comprehensive, analytical and thoroughly researched studies. Facts and Statistics.
One notable example of this type of evidence-based approach is the work of John Correia from Active Self Protection. As of today, Correia has carefully analysed over 175 incidents (robberies, muggings, attacks, etc) caught on camera.
To a lesser extent (26 incidents), Rener and Ryron Gracie have done the same but with a focus on grappling situations. You’ll find the videos (along with the analysis of 62 UFC fights!) on their youtube channel GracieBreakdown.
The detail examination of CCTV and surveillance footages of knife attacks offers invaluable lessons.
And here is what I’ve learned:
KNIFE ATTACKS: AN ANALYTICAL STUDY
Data for this research has been gathered and compiled from 150+ knife incidents caught on surveillance and phone cameras.
All the videos are accessible on my youtube channel in the following playlist: Knife Attacks (CCTV).
More videos will be added through time and statistics will be updated.
Let’s get started,
71.1% of knife attacks are led with the empty hand
The fact that, during a knife attack, aggressors usually lead with their free hand, while keeping the knife close to their side, was first pointed out in 1988 by Don Pentecost in his contentious book Put’em down, take’em out! knife fighting from Folsom prison.
Back in the 80ies, Pentecost simply and brutally shattered a number of popular myths and preconceived ideas about the use of knives in real life situations.
Most commonly (71.1% of the time) aggressors will lead the attack with their empty hand, effectively shielding the knife, such as in the following video (segment starts at 0:21):
As Pentecost also clearly stated, the empty hand is not a dead, “paralyzed“, hand and attackers will use it to strike or, more commonly, to grab the victim.Indeed, when aggressors lead with their free hand, 80% of the time they will also use it to latch on the victim:
This use of the empty hand (also known as ‘leveraging arm’) greatly changes the dynamic of the fight. Particularly because your first reaction, as a victim, will be conditioned by the movement of the aggressor’s empty hand (more on that in Part 3).
But the prime lesson though is that most of what is taught in the Martial Arts and RBSD industry (i.e. attacker leads with the knife, no grabbing, no forward pressure) doesn’t apply to the vast majority (70% +) of real life knife attacks.
Most knife attacks are ambushes, not duels
For the same reasons bad guys will use a force multiplier such as a knife -i.e. they don’t want a fair fight but an easy prey- they’ll make a surprise attack on you from a ‘concealed’ position or with ‘concealed’ intentions.
And you probably won’t see it coming.
As you can observe in this CCTV footage, the saleswoman was ambushed and cornered. She stood absolutely no chance.
The aggressor didn’t threaten the victim. Instead, he kept his weapon concealed until he struck the woman. Clearly, his intention was not to try to get what he wanted through intimidation/coercion but to eliminate the saleswoman.
“Victims who survived a violent confrontation against a knife-wielding assailant consistently reported that they were completely unaware of the existence of the weapon until after they had suffered stab or slash wounds. In essence, these survivors of edged weapon attacks state that they believed they were engaged in some sort of fist fight; only later, after sustaining injuries, did they realize that the assailant was armed.” Imi Lichtenfeld (Krav Maga founder)
In 80% of the cases I’ve analysed, the knife is kept hidden until the very last moment. That is until the attack is launched.
Aggressors will try to distract the victim and wait for a good window of opportunity to strike and won’t hesitate to attack the victim from the back.
Situations with multiple attackers seem less common with only 11.4% of the incidents I’ve reviewed.
The following video (segment starts at 0:31), shows the ambush of a store clerk:
In a typical way, the victim is 1) distracted, 2) cornered, and 3) the attack is launched at close quarters.
70.6% of knife attacks are launched within 3 feet of the victim
Knives are short range weapons, so it doesn’t come as a surprise that 70.6% of knife attacks start at conversation range.
It’s important, though, to stress that “within 3 feet” really means “at arm-length or less”:
This leaves you with very little space (and time) to react!
Such a small ‘reactionary gap’ means that it’s almost impossible to stop the first stab if you’re not expecting it.
This is why it is so important to maintain distance and keep control of the space when you’re in a confrontation (see here an interesting article on Space Management in Self Defence)
As aggressors so often lead with their free hand (usually the left one), victims end up being stabbed in the neck, like in the video above, or to the chest on their left side (where the heart is located!).
Knife attacks are fast and furious
Another consequence of such close-range attacks is that victims tend to fall as they move backwards trying to escape their aggressor.
This is the case in 55% of the incidents I have analysed:
This way of charging a victim, as seen in the video above, is known as a “prison yard rush” (or “prison knife rush”). It was made notorious in the Martial Arts industry by Don Pentecost in 1988.
In his then-contentious book, Pentecost further points out that someone who is attacking you with a knife is trying to kill you.
They won’t hold back, they won’t hesitate.
They will go after you like mad dogs.
“Research tells us someone willing and ready to carve you up like a thanksgiving turkey is far different than someone with a gun […]“Hank Hayes (Knife Defence 101)
Here is an illustration of these points with an interesting analysis by John Correia from Active Self Protection:
As you can see in this video, the aggressor goes full on with ruthless determination in an attempt to overwhelm his victim and cause maximum damages as quickly as possible by whatever means necessary.
Knife attacks don’t last long
Indeed, the average incident time for knife attacks, from the moment the attack is launched to the moment it stops, is 23 seconds.
“The time frame of a knife attack is usually very short – it is often over in a matter of seconds” Don Pentecost
The median time is 14 seconds which means that half the attacks last 14 seconds or less.
But 80% of all attacks last less than 32 seconds:
The graph shows a sharp increase in numbers up to 23 seconds indicating that most attacks (70%) last 23 seconds or less.
After that point, the curve starts to flatten and reaches 90% at 59 seconds.
It’s interesting to note that, although it takes 9 seconds for a 10% increase to 80%, it then takes 27 seconds to complete another 10% and reach 90%.
What this means is that if a knife attack lasts 23 seconds, you have a fair bit of chance that it will go on only 9 more seconds. But once a knife attack reaches the 32 seconds mark, the same “fair bit of chance” may requires an extra 27 seconds.
In other words, if a knife attack goes on for longer than 32 seconds, it is more likely to last a lot longer.
Did you notice how the curve seems to go up again around 45 seconds instead of plateauing as expected?
Let’s visualise the data differently,
The following graph shows the number of knife attacks plotted against time. To make it clearer, I just show the trendline:
There’s a peak in the number of attacks around 7 seconds with 25.2% of all attacks lasting between 5 and 10 seconds, and half of all attacks lasting 14 seconds or less.
Now, what that tipping point seems to indicate is that if you can hold your ground for 7 seconds during an attack, the aggressor is more likely to give up.
The fear of being caught is likely to be an important factor that keeps knife attacks very short.
Obviously, the longer an attack is carried, the more likely someone -including the police- will intervene.
In that regard, it is interesting to note that 55.9% of all attacks are stopped by the intervention of a third party.
But here is the fascinating part,
From the 7 seconds mark, the number of attacks goes down sharply to reach a minimum at about 45 seconds and then goes up again.
What the graph shows is that there’s a second tipping point around 45 seconds after which a knife attack will tend to go on much longer. Most commonly an extra 14 seconds. More than half of the “over-45-seconds” attacks last between 53 and 66 seconds.
Although it is hard to infer any solid evidence from such a small number of cases, it seems that third party intervention occurrences are much lower in the 45-seconds + group than in general.
In other words, these attacks lasted longer because no one intervened.
Unsurprisingly, attacks by ‘psycho lovers’ -who don’t care much about being caught- seem to be concentrated in this group as well.
Although the average duration of a knife attack is 23 seconds, it is important to keep things in perspective.
In that short amount time, the average attacker will stab you at a rate of 5 to 7 times every 5 seconds!
Knife attacks are more often performed with quick, short, repetitive stabs at different angles
Commonly, there will be a first wave of stabs during which the attacker, taking advantage of the surprise, will land between 5 and 10 stabs. Then, as the victim fights back trying to escape, the stabs will be spaced-out.
The more you get cut or stab, the more chances a vital organ, such as the heart, or a major blood vessel, such as the carotid artery (neck), will be hit which would result in a quick death.
As you can witness in the following surveillance video, things can go really fast. The first victim is stabbed twice between 0:03 and 0:06, and totally collapses less than 40 seconds later!
Sure, many people have survived a greater number of cuts and stabs. But the unavoidable truth is that you only need one to die!This is an important point because most attacks are not a ‘single straight thrust’ (i.e. bayonet thrust type of motion) or a ‘wide sweeping stroke’ (i.e. slash).
Knife attacks are predominantly executed with quick, short, repetitive stabs at different angles (e.g. switching from low, upward, stabs to the chest, to high, downward, stabs to the neck).
Also known as the “sewing machine” and “prison shanking”, short rapid stabs are very difficult to stop because there is not much time and not much space to ‘deflect-and-redirect’ the attack or ‘block-and-strike’.The majority of attacks are carried out using a regular grip (58.8%) but the reverse grip (also known as “icepick grip”) is, at 29.9%, more frequent than commonly thought.
In a small number of cases, around 6%, the aggressor changes his grip during the assault, moving from regular to reverse or vice versa.
It’s worth noting that I’ve not seen any case of hand-swap (i.e. knife being moved from one hand to the other).
What have we learned?
In this first part, we’ve seen that knife attacks are most commonly ambushes, launched at short range (within 3 feet of the victim).
They are extremely violent; carried with speed and determination within a very short span of time (i.e. they don’t last long).
Attackers will lead with their free hand, effectively shielding the knife, and will stab the victim repetitively with quick short thrusts at different angles.
Attackers frequently grab and push the victim who quite often will fall to the ground.
In other words:
- you will be taken by surprise and you will be overwhelmed by fear and aggression
- you won’t see the blade before the attack is launched
- you very likely won’t be able to run away and avoid the attack
- you will have very little time and space to react and deploy a counter-attack
- you probably won’t be able to stop the first stab(s) so, yes, you will be you will be cut and stabbed a number of times but you might not even realise you’ve been stabbed (which is why you should always check yourself for wounds after a physical confrontation)
- you probably won’t have time to draw your own weapon (gun, knife, kubotan keychain, pepper spray, etc); at least not before being stabbed a couple of times
- you will be likely moving backwards, your balance will be compromised, and you’ll probably fall to the ground
- your movements will be restricted, your fine motor skills will be gone, you won’t able to access the knife bearing arm easily
- any technique that is based on smooth arm deflection and manipulation has very little chance to work
- any technique that rests on the assumption of a single straight thrust (‘full-stop one-step zombie attack’) or a wide sweeping slash has very little chance to work
These results should definitely inform our training methods and I will expand on that point in Part 3: “Knife Defence – Empty-hand Techniques”.
But the nagging question at this point is “how do people survive knife attacks then?”