Policing the Margin
So the traffic cops are extending their 4km-only tolerance limit until the end of the month and are looking at making it permanent. This has a feeling of pre-concieved inevitability about it. Although Acting Superintendent Rob Morgan assures us that the permanent adoption “will really be an evidence-based decision”, we all know that this is complete nonsense. There is absolutely no evidence that a reduced tolerance limit will do anything except increase police ticket revenue.
Speed limit enforcement at the margin makes little or no difference to the accident rate
”Let’s face it, whether a driver is doing 104 or 110 kph will make no real difference to accident statistics. While there is good evidence in controlled accident situations (with crash test dummies) that increased speed increases the risk of fatality, there is no reliable evidence that this is true on the open road. Empirical tests such as these are done at relatively low speeds using a test bed and a solid wall. The results are then extrapolated to high speeds, an extrapolation that is not necessarily valid, given that there are a great many other factors at play in a real traffic accident.
There is also some epidemiological evidence that increasing road speed limits increases fatalities. The repeal of the national road speed limits in the US allowed states to increase limits as they saw fit. The resulting increases did see a rise in road fatalities with a 4% average increase in speed purported to produce as much as an 17% rise in fatalities. However, most of this fatality data does not take into account traffic volume. When traffic volume increases are factored in a 10mph increase in speed limits may produce a 1.3% increase in fatalities. Not insignificant, but small potatoes compared to the enormous gains made through better, safe vehicles and roads.
I am not arguing here that speeding does not cause an increase in accident fatalities, but that speed limit enforcement at the margin makes little or no difference to the accident rate. Where speed is a significant factor in an accident, it is almost certainly excessive for the conditions. I strongly suspect that the accident rate (and, probably the fatality rate) of a late-model BMW cruising at 120kph down the (very straight) N1 freeway south of Auckland is going to be much lower that the accident rate of the jalopy with marginal tyres and shocks trying to navigate the Coromandel at the posted speed limit. Similarly, the logging truck doing 95Kph between Tokoroa and Taupo is considerably more dangerous than the MacDoctor doing 110 in his 4-year-old Hyundai Sonata on the same road. Of course the idiot doing 140Kph on that road would be more dangerous than both of us, regardless of his vehicle.
I would submit that it is not particularly useful policing speed limits, in road safety terms, when it is clear that our police ignore most careless driving incidents in favour of writing out speeding tickets. From a policing point of view speeding tickets are a whole lot less paperwork than dangerous driving tickets. Most speeders pay their fine and the case is closed. Some go to court but usually the cop in question just has to provide the written proof that the camera was calibrated and that the vehicle was properly identified. Dangerous driving, however, carries stiffer penalties and often requires the personal presence in court of the policeman who wrote the ticket. It is small wonder than, that the police prefer the simplicity of the speeding ticket, despite the fact that it contributes little to road safety.
This preoccupation with speed may well be a contributor to the reputation of Kiwis for aggressive, discourteous driving. After all, it is very rare to see anyone being pulled over for changing lanes dangerously on the freeway or even overtaking on a corner or blind rise. In fact, I cannot recall seeing anyone being issued a ticket in this country for anything other than speeding, parking or, that other favourite revenue-gathering exercise, failing to come to a complete stop at a stop sign. Anecdotally, a friend of a friend once told me they were ticketed for running a red traffic light – the only ticket I can recall ever hearing about that had something to do with genuinely dangerous driving.
If the police really wish to make further inroads on road safety, they need to stop mucking around at the margins of the speed limit and determinedly go after those few drivers who drive in a genuinely careless and dangerous manner.
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Feb 9 12 3:23 pm
It’s no wonder we have inconsiderate drivers when police themselves do not set the example. I drive a lot as part of my job, and see police cars (simply cruising about, not on callout with siren and lights flashing), changing lanes without signalling, driving through amber lights, not coming to a halt at stop signs, you name it. The other day I followed a police car through a roundabout and shouted “hallelujah” when he actually signalled his exit, the first I have seen to do so in years. They also are not interested in policing the loud “boy racer” exhausts either, despite the fact that NZTA claim that they have an agreement with them to be tough on reported examples.
Feb 9 12 4:26 pm
About 10 years ago I was following a car that did 50 in a 70 zone then 50 in 100 zone. I was running late and new the road so “floored” it coming up to a small straight stretch. However being a 1.3l car with two adults flooring it didn’t really lead to much acceleration. The car in question then decided to accelerate up to 100 km leaving me to slowly pass.
As I was finishing the maneuver a police car came around the corner and there wasn’t much space between the corner and I (though he likely didn’t have to break). Got booked for overtaking without 200m remaining. (I didn’t argue the point, but in retrospect I think I might do now, though I now mostly have more patience even when running late). This occurred on rural Waikato road.
about 15 years ago my wife who was in a fowl mood, jumped the gun on a roundabout and cut off a cop car (I only heard about it, so don’t know how close this was) and got a ticket for failure to stop (I think ?). This was in Hamilton.
So I don’t know if our driving has improved or policing has reduced (I suspect a bit of both)………..
Lastly this week coming home I was “randomly” pulled over by a cop. Was in the middle of a line of traffic on SH1 in Huntly. No to sure why he chose me, he had a very close look at all the bits of paper and took time to check that all correct back at HQ. In the end he said, please don’t travel to close to car infront (I didn’t think I was any different to any other cars in the line, but might have been closer at that moment). Both me and my wife have been pulled over in Huntly with that car for seemingly no reason so we think there could be some connection with a local “bad” person who has a similar car, or maybe it is the ding in the back and coat hanger areal that marks the car as high likely hood of being involved in nefarious activity.
Feb 9 12 4:48 pm
Sounds like you are being “profiled”…
Feb 9 12 7:38 pm
It’s interesting that according to you the laws of physics don’t count when they’re not convenient and yet you can say without a hint of irony (or evidence):
“This preoccupation with speed may well be a contributor to the reputation of Kiwis for aggressive, discourteous driving.”
No wonder you have such odd views on other matters if this is the “reasoning” you’re using.
Feb 9 12 10:17 pm
Sigh. Still battling with reading are we, Judge?
I am not arguing here that speeding does not cause an increase in accident fatalities, but that speed limit enforcement at the margin makes little or no difference to the accident rate.
So. No suspension of the laws of physics at all.
This preoccupation with speed may well be a contributor to the reputation of Kiwis for aggressive, discourteous driving.
The tentative, provisional nature of this suggestion makes evidence rather superfluous. I am merely suggesting that concentrating on dangerous driving instead of minor increases in speed may assist us in becoming a nation of better drivers. Hardly earth-shaking or bizarre.
Feb 10 12 7:08 am
You hold yourself to a considerably lower standard to those you attempt to criticise. They produce at least some evidence to support their position. You make a silly assertion and squawk that evidence is superfluous.
I am merely suggesting that concentrating on dangerous driving instead of minor increases in speed may assist us in becoming a nation of better drivers. Hardly earth-shaking or bizarre.
Except you have provided no evidence or data to demonstrate that this is true or that the police don’t concentrate on dangerous driving, other than the anecdotal claim that you’ve never actually witnesses them doing it. Think about why that might be.
Feb 9 12 10:59 pm
Totally support your analysis MacDoctor; there seems to be a total disregard by the police of dangerous driving which can occur at any speed. I won’t rabbit on about slow vehicles/passing lanes etc – we’ve all experienced those frustrations. Low hanging fruit comes to mind (as you imply).
I often see a hand-held laser gun-equipped cop on the northern motorway at the Oteha Valley Rd exit (going south). This is just over the brow of a hill, ie a blatant speed trap. What bothers me is not so much the trap itself, but the dangerous position of the car parked at right angles to the motorway on the safety triangle. If someone exited a little late it would all end in tears.
Another example, just today: two cops with a handheld camera on Pakuranga Rd at the lights facing Ti Rakau Drive, during the evening rush hour. Presumably targeting red-light jumpers, so anyone silly enough to do that in their full view deserved a ticket! But improving road safety? – I don’t think so.
Disclosure: I got 2 speeding tickets about 40 years ago, and one more about 5 years ago (of which I am immensely proud, as the kids were convinced I was an old fuddy duddy). All on the open road btw at around 15 km/h over the limit and no danger involved, but all fair cops vis a vis the speed limit. With the last one I discovered I could have driven at 119 km/h for the same price, so didn’t get full value there.