When it comes to speed, speeding or the slogan “speed kills” everyone has an opinion. Just ask any “expert” at a Friday night gathering around any fire or bar and you’ll have as many opinions as you do people present. There are some pretty convincing arguments either way, if you are sober enough to listen to the self-imposed expertise of all those around you But what if you really are an expert.


If you have ever gathered around a fire with Stan Bezuidenhout, a forensic road traffic collision reconstruction expert from IBF Investigations, you’re likely to be in some pretty good company when it comes to expertise in this field. Now, we’re not just talking “maths” here. Stan has experience that reads like a who’s who of road traffic collision analysis. Having personally attended thousands of crash scenes – more often than should be the case involving speed and even illegal street racing – he knows a thing or two about the aftermath of these types of collisions. He is also one of the leading experts in South Africa when it comes to the actual discipline of reconstruction – the analysis of collision as a function of evidence, dynamics, energy, forces and effects. As a reconstructionist, it’s his job to assess damages, consider dynamics, measure crush, calculate forces and make determinations about cause. He then testifies to the causes in court, and he is well known for it.

So what would a real-world expert with experience in many countries, many disciplines, many courts and many cases have to say about speed? Would he agree that speed kills? Would his experience lead him to a natural conclusion that many would share? What would his thoughts be on speed enforcement? Would he be able to say how big an issue speed really is, when it comes to the unacceptably high rate of carnage on South African and many other African roads?

We had opportunity to ask Stan exactly this and here is what he had to say:

“(Giggles)… Well, you will probably be shocked to hear me say that I completely and utterly disagree with all current opinions on speed and speeding on South African roads. I cannot for one moment believe that you can blame speed for anything, since it is nothing more than the movement of an object within a defined time period. We refer to it more often as velocity than speed, when considering it in a scientific frame of reference. But the fact is that I have two opinions. I have a personal one and I have a scientific one.”

Stan leans back, relaxes, but his eyes glow with focus. This man can think on the fly, he has a plethora of facts right at the tip of his tongue and he loves this stuff. His passion is contagious …

“On a personal level I fully understand that the slogan speed kills could be used to promote road safety. It’s short, it’s catchy and it flows off the tongue rather easily. You can share the thought on almost any platform and in any medium quickly and, as far as lay references go, it seems credible. But it’s nothing more than a good marketing slogan. The problem with placing marketing people – business people – in charge of creating a campaign slogan that will effectively address road safety awareness is that you will get results. Sales. Awareness. Repetition. Buy-in. As a marketing strategy, it’s brilliant. We’re at the stage now where everyone knows speed kills. It’s become an accepted rule, almost. And here comes the sale part: If everyone knows that SPEED kills, and then surely knows that we must enforce not SPEEDING and therefore fines – the sale – is justified and even supported. People have bought into the product.”

OK, wait. If Stan is a crash expert, why is he now talking about marketing and business as if he knows more about that or considers it a bigger issue? Well, Stan also studied hypnosis, handwriting analysis, cognitive interrogation and associated psychology and he is auto-didactic (we didn’t know what it meant either). An auto-didactic is someone who studies without the need for tuition and gains knowledge to an equal or even higher standard than those tutored in a particular field. But we digress and Stan carries on …

“I know this sounds counter-intuitive. I know that the slogan has become so popular and the content seems so logical that people no longer even think about the validity or the implications of the slogan. But you could not be more wrong. Speed, as I said, is a function of space over time. Nothing more, nothing less. In order for the slogan to make any sense, it should include reference evidence and exclude the contrary. Simplifying it and trying to make speed the villain – often at the expense of other more dangerous road transport infringements – is actually irresponsible. I am waiting for someone to prove to me that a reduction in speed necessarily results in an improvement in road safety. Now don’t get me wrong – I’m not talking about the relative speed of a car, as a function of traffic friction here. I’m talking about speed in isolation.”

Wait what? Traffic friction? That’s a term we’ve never heard before. We interrupt Stan to ask about this. Sounds like insider jargon that has nothing to do with the actual topic of discussion. Stan smiles again. We can literally see the cogs turning now. We’ve touched on a subject that he is passionate about.

“Traffic friction is not just a general term. Oh no. (That smile … Is he mocking us now?) Traffic friction is a term that describes a very specific set of road transport movement dynamics. Let me simplify it. (Oh ok, he’s not mocking us. He’s just enjoying the opportunity to explain). Think about peak hour traffic with lots of cars heading in the same direction. Scientifically, they should all move at the same speed – probably the posted speed limit – and simply proceed without incident, unless something substantial happens. Now you have one guy who is on his cell phone. He slows down to concentrate on the call. Now others start to slow down and it cascades rearward as everyone responds to the changing traffic pattern up ahead. Some people start changing lanes to get past slower traffic and this causes more cars to slow down.

“Because there is now a gap ahead of him, more start to change lanes to essentially exploit this space. Traffic friction interferes with the smooth flow of vehicles on a road. There are many things that cause traffic friction. A good example is road use psychology. Some people consider themselves safe drivers – they drive below the speed limit if they think it makes them feel safer. Others are in a hurry, so they exceed the speed limit. Other have nice cars and enjoy speed, so they drive faster. Some are distracted by cell phones and are therefore distracted and either driving slower or venturing out of their lanes. Vehicle design differences – trucks versus light motor vehicles – also contribute. Some people drive at the speed limit and brake and drop well below it every time they see a speed camera or traffic officer. Traffic friction. Everything that causes an interference in smooth traffic flow.”

We have to interrupt Stan here. He tends to get a bit passionate. This is an article about speed, after all … He gets back on track…

“To get back to this speed kills business – essentially, speed as an isolated element of traffic movement does not kill. If this were true, racing drivers, pilots, astronauts and everyone achieving higher speedshould be killed more often. But we all know the opposite is true. Race tracks can easily be described as the safest places for drivers to be. True – they all drive in the same direction and they’re all more experienced, alert, focused and skilled, but you get the point. For the slogan to be both accurate and relevant, it should probably be changed to a greater change in velocity results in more serious injury.

“Sure – that’s not a great example as marketing slogans go, but it is certainly more accurate. When it comes to crash analysis, the severity of the collision can be divided into two aspects: the change in velocity – called Delta-V and the results. When an object changes from one velocity to another within a specific time period, that rate is expressed as Delta-V. The change in velocity, over time. The more severe the Delta-V, the greater the amount of energy involved in this change. This is why falling out of the sky from 3 000 meters onto a big catch-net does not kill, while falling on concrete from just 30 meters does. The rate at which you are slowed down – not the speed at which you were moving.

“As far as results are concerned, any serious or incapacitating or fatal injury is relevant. A 30-ton truck rolling back at 40 km/h and crushing a man against a wall and a 300 kg motorcycle striking him at 100 km/h could both result in a fatality at vastly different speeds. So no. Speed, does not kill. Energy does. Momentum. And the rate of change from one velocity to another in collisions. This can also be positive or negative: you can strike something and decelerate really quickly or get struck from behind and accelerate really quickly – change in velocity. The propensity for something to want to keep moving until something stops it or stay still until something starts moving it, is contained in well established natural laws; Newton’s laws. Whether we consider the mass and velocity of the truck or the motorcycle, one thing is a certainty: while the motorcycle killing someone would be considered proof that speed kills, the truck would have done exactly the same but the slogan no longer seems appropriate. Speed kills is therefore a subjective reference and by design, flawed.”

We’re now getting dizzy. Energy, joules, velocity, Traffic friction and all this slogan talk. We ask Stan to get to the point, and he does as he continues but there’s just no end to his passion and we’re becoming quite inflamed by it now…

“Take speed law enforcement. If you accept the slogan speed kills as a fact, you have a short route to the next level of logic: More speed kills even quicker and less speed kills less. Ergo, let’s clamp down on speed. Let’s focus on speeding. In order to do this, we need to define some parameters, right? That’s easy: speed limits. Let’s say people are just not listening and too many people are dying on a road with a speed limit of 60 km/h. We start introducing speed cameras and we get really tough on offenders – we start issuing fines of higher value, adding demerit points and start arresting people. That should work, right? Not so much, if you look at most results. In almost every case where there is an increase in speeding fines, there is not a proportionate decrease in the offense rate. That’s because of a concept called the 90th percentile. It refers to the way 90% of people would act on a particular road. The trend, as it were.

“People tend to act in a way that seems socially acceptable or prevalent rather than in a way that is necessarily legal. If everyone is misbehaving, more people are inclined to do the same. There is research that showed when people are waiting at a red traffic light, more people are willing to cross against the red if a person in a business suit does so first than if a person in plain clothes does. We follow trends. Human psychology is infinitely more complex than mere legal restraint would imply. Take the change from apartheid to a democracy as a speaking example of the power of group mentality and civil disobedience. The e-tolls is another example of the power of group influence. No matter the sphere of reference, the old bigger stick argument simply does not work if there is no carrot at the other end.”

Stan is now getting somewhere and we’re starting to wonder if he’ll accept an invite to our next office braai. This is a guy you want around the fire.

What are his thoughts on other things? His thought processes seem so well defined. Now we’re getting passionate. We nod attentively and allow him to carry on…

“If you take children in school as an example and compare it to the prevailing efforts in road safety, you will immediately see the dichotomy we’re faced with: During your whole school career and upbringing, there’s no corporal punishment, almost every form of discipline is considered to be torture or abuse and children are taught to just try harder next time. If schools were run like road safety campaigns, it would sound something like this: Children, we’ve repeatedly told you that you must arrive at school at 8, attend all classes, achieve high marks, sit still, listen to your teachers, wear full uniform and do your homework every afternoon. After seeing that you are not listening, we will now be taking your lunch money if you arrive late, we will not allow you to go to lunch and eat, you will have to walk to school and we will name and shame those who commit offences.”

This is a huge statement. Stan pauses and looks at us. His expression urges us to consider this comparison.

While it is totally preposterous, it really seems to be similar, doesn’t it? We are not even allowed to discipline our own children; we have to use positive reinforcement for everything and understand and nurture their individuality. At the same time, we are expected to perform in all aspects of road safety under threat of ever more serious consequences. By why doesn’t it work? Stan has the answer…

“Every research effort has shown that you can train animals, children and even adults better by using positive outcomes-based and reinforcement methods. You can teach a dog to sit by beating it until it does, but you end up with an unhappy, dangerous dog. Nothing more. There is no respect, no love, no trust and no positive relationship. Why do we refer to road traffic research all the time but we fail to agree on this one universal truth; harsher punishment is never the answer, no matter the motivation.

“Imagine a country where the law is designed to empower and enrich people – not govern and intimidate them. Let’s call it Stanada. In this country, if you are caught speeding, you are not penalised financially. Instead, you are subjected to an immediate (roadside) training programme. You enter a facility and you are forced to watch a 1 hour documentary on the dynamics of speed in collisions. You undergo training. At the end, you write a test – and you stay there till you pass – that actually confirms that you understand the implications of speeding. This does two things: It educates reactively in a relevant sphere of reverence and costs you the one commodity that is equally valuable to everyone: time. You pass your test and you’re allowed to go. No money taken, education provided and all future excuses for speeding eliminated.

If you are now ever involved in a speed-related collision, you are immediately accountable – even if you are not the primary cause.

“Over your driving lifetime, you are likely to receive a variety of training courses, ranging from the effects of speed, to stopping at stop streets, wearing seatbelts, etc. I have huge problems with fines. It is by design unconstitutional and unfair. How is a R500 fine for a single mother of three in any way equal to one given to a business tycoon and billionaire? Oh sure, you can take away licenses, but now the single mother can’t go and get medicine or get her kids to a doctor and the billionaire can just hire someone to drive him around.

“Imagine a country where the law is designed to empower and enrich people – not govern and intimidate them”

The punishment model is essentially a class-based system where the lower income class suffer while the rich enjoy the privilege.”

We urge Stan to get to the point. This is very interesting, but we want to bring him back to the issue of discussion: Does speed kill?

“No. Speed does not. If we are going to consider whether speed kills, we also need to explore how this affects people. Will truck or bus drivers act any different if they’re driving at 80 km/h? This is not really speeding as we know it, is it? I think the whole speed kills claim should be revisited and – along with it – all thought processes associated with enforcement, compliance and risk mitigation. I would say that ATTITUDE KILLS is a far better slogan and this is something we should adjust first. In Germany, on the autobahn, the collision rate is not considerably higher than on any roads with speed limits, but this is not due to strict law enforcement but rather to the attitude of the kinds of people – the culture they’re dealing with.”

We thank Stan for his interesting insights and promise to explore a follow-up argument. Stan promises that he can talk about this for days and that there are many other aspects of speed and speeding he has not even been able to cover. We look forward to hearing more. Maybe around a fire, with a beer in hand. Soon, we promise.

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Issue 66


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