WHAT IS ACCIDENT RECONSTRUCTION?
A. Criminal and\or Civil Cases
When a driver is charged with culpable homicide or reckless and\or negligent driving, the state must proof that the driver drove his vehicle in a willful and wanted disregard to the safety of other road users. This has to be proven beyond a reasonable doubt.
Defense attorneys will try to proof that the driver drove his vehicle like a prudent driver, by driving inside the legal speed limit, by keeping a proper lookout, by keeping a safe following distance and so on.
In civil cases it is easier as a case is won or loose on the balance of probabilities. In civil cases there might also be contributing negligence and a proportion of liabilities.
It is clear from the above that speed plays a huge role in the determination of recklessness and\or negligence.
1. Pedestrian, motorcycle and cyclist accidents.
In pedestrian accidents the court wants to establish if a driver kept a proper lookout. Did he reduce speed when he first saw the pedestrian? Did the pedestrian run or walk across the road? How far away was the vehicle from the pedestrian when the pedestrian started to cross the road?
The time it took a pedestrian to move from the pavement into the road and up to the point of impact can be established by using a similar aged pedestrian to cross the road and time him\her with a stopwatch. Velocity is equal to distance divided by time. By changing speed that is measured in km\h to velocity that is measured in meters per second, the time the driver had to avoid the pedestrian can be calculated. It has to be taken into account that it takes 1.5s perception\reaction time for a driver to apply emergency brakes and 1 second to swerve.
It is possible to determine the time it will take a vehicle, travelling at a speed, inside the legal speed limit of the specific road, to skid to a complete stop. If the calculated time, plus the perception\reaction time is to little, the driver of the vehicle cannot be held accountable for the accident.
If, however there was adequate time for the driver of the vehicle to have stopped in time, but due to his\her excessive speed, the driver can be found guilty of reckless driving.
The speed of a vehicle in pedestrian accident can be determined by the length of the skid marks left on the road surface, by using the skid to a stop formula. In the case of vehicles with ABS that leaves no skid marks, the speed of the vehicle can still be determined using projectile motion analysis whereby the distance the pedestrian was flung through the air till its landing becomes essential.
In motorbike and cycle accidents the speed of the vehicle can also be determined by projectile motion analysis again requiring the distance the cyclist or motorbike driver travelled through the air from point of impact to landing. The launch angle of the rider is also required and sometimes the weight of the rider and vehicle involved.
2. Single motor vehicle accidents
In the event of a single motor vehicle accident for example a vehicle that went into a yaw, left the road surface and rolled. The speed of the vehicle prior to it leaving the road surface can be determined from the radius of the yaw marks left by the vehicle on the road surface. The driver of the vehicle may have exceeded the critical curve speed of the curve he\she is trying to negotiate. The critical curve speed is the maximum speed a vehicle can safely negotiate a turn based on the radius of the curve.
When a vehicle leaves the road surface and collided with a fix object for example a tree, the speed of the vehicle can be determined through crush analysis. In these cases, the amount of crush damage that a vehicle sustained must be accurately measured. Stiffness coefficients are then uses to determine the vehicle’s speed at impact.
3. Two or more vehicle accidents
In cases where two vehicles collide and there are pre-impact skid marks by either or both vehicles involved, the skid to a stop formula cannot be used to determine the speed of the vehicles involved as the vehicles did not skid to a stop, but collided with each other.
Linear momentum equations can be used where one vehicle collided with another head on or rear end. In these cases, the weight of the vehicle and its occupants are required.
In accidents at intersections where vehicles collide at an angle, the speed of both vehicles at impact can be determined by using any angle momentum equations. In these cases, the weight of the vehicles including occupants, the approach angle and departure angle of each vehicle, the distance the gravitational center points of the vehicles travelled from point of impact to its final rest positions is required.
B. The importance of a scale plan
A scale plan of an accident scene allows a reconstructionist to accurately plot the point of impact, the skid marks and the final rest positions of the vehicles involved. Accurate measurements can be obtained from the scale drawing which are used in above-mentioned formulas to determine speed. With the damage profile of vehicles, the principle direction of force can be determined and the vehicles placed in the exact position it was in relation to one another at point of impact.
It is clear from the above that an accident scene contains an enormous amount of physical evidence that can be used by a reconstructionist in determining speed and ultimately liability in any traffic accident. It therefore of extreme importance that whoever attends to an accident, to record, photograph and measure all the evidence on the scene and to draw a scale plan of the accident scene.
The damage to vehicles must also be recorded and photographed in order to determine the principle direction of force.
When a reconstructionist are instructed to do a reconstruction years after the accident occurred, the reconstructionist have to measure the road layout in order to draw a scale plan of the road layout at the accident scene. He\she then uses the SAPS sketch plan and the key to plan if available and by using the same fix point\s as the SAPS draughtsman plot the accident scene to scale on the road layout that was drawn to scale.
It is important for persons involved in serious and fatal accident to appoint a lawyer to defend them if necessary or a lawyer that specializes in claims against the RAF as soon as possible after the accident. This will allow the lawyer to appoint a reconstructionist as soon as possible in order for the reconstructionist to attend to the accident scene.
The reality is that accident reconstruction is a science, but it is in most cases possible to determine exactly how and why an accident occurred and who was to blame.
Reducing the Accident Rate
Take note of the figure for speed 15.2 %. It is low in percentage as we said, yet it is all they do.
The black driver issue is not new to me. It is the same for Namibia. I am looking and working on the Namibia issue along these lines for some time now and is trying to study it there. My thinking and experience in Namibia is :
I think the black driver issue has to do with the Previous disadvantage story. Black drivers in general were not exposed to the background and standards of a society growing up with higher level of driver skills and responsibility linked to accountability. Nor the level of technology in cars, standard of living and so on and, so on.
The explosion that took place in the growth of black people in general and on all fronts since independence in both SA and Namibia has had an impact on reaction and outlook towards life and behaviour on certain people . Can one call it the “Free for all sort of attitude” ?The number and increase in driver numbers and car owners figures are also self explanatory. I am not advocating this statement applies to all. How to establish this in a percentage? I don’t know.
It is followed by poor enforcement ,accountability and follow through from the justice system. I regret making this statement .But sure as hell it needs to be looked at The word working at “grass root level” linked factual evidence with accident analysis, I am ready to be challenged on this point. I admit study needs to be done to get to the bottom of it and understand the depth of the issue at hand.
In Namibia and most accidents are caused moving violations .A total disregard for adhering road rules. Hence ,attitude. Then, as a secondary impact to the initial moving violation the accident degree of severity is aggravated to a higher level due to speed. Speed is not always the cause initially.
Looking at the stats in Namibia, we question the quality and accuracy recording the cause accident stats. The police level of training and knowledge in this regard is not what it should be. I am not sure how accurate the data recording is in SA . The ones I have been exposed to here was not good.
This behaviour I am talking about also trickled through and exist in other areas of society also. The stats are there for all to know and see. The road usage is just another extension arm of that behaviour, it is worse than the criminal elements of those stats on record!!!
I am not surprised at that figure for black drivers. The worst is, as is the case in Namibia all in society in general are following taking the attitude if the “taxi style driving” can get away with it! so will I. In the absence of enforcement people do get away with it.
This behaviour evil has spread to more than what we think, Hence, we are where we are. I made a statement in Namibia. We also need psychiatrists and psychologist on the team to resolve the problem.
Attitude is the number one killer on our roads !!! It comes in a number of different formats with drivers on the road. Each group with their own set of regard and disregard to other road users, the law and accountability.
The trick will be to identify the various groups and handle and educate them accordingly in order to get all on the same page subject to the same rules , the same enforcement and justice system. No matter who you are.
A speed camera and road block cannot address attitude. That is the real problem we need to address. It is absurd to have lost so many lives on our roads in what 20 days only.
I think the minister is now getting on the correct path or track. I also admire her opening statement. Nobody before her got near the issue at hand. Traffic and departments with the framework or structure within cannot solve the problem alone. They could not over the years do so. The minister must surround herself with a team of experts in conjunction with traffic and establish an action plan dictating to the role-players what the demand is and secondly, lay down the a time frame of implementation once set . She will have to get the justice minister involved also.