When a police officer stops you on the road to issue you a ticket for speeding and you’re only 20 km/h over the limit on a major highway, generally the real reason you’re receiving the ticket is not one of safety. If the issue was safety, your licence would be taken away, your car would be impounded and the fine would be much higher.
This is what is done (in Ontario at least) when someone is caught speeding 50 km/h over the limit. We rightly think that this is dangerous behaviour, and the coercive powers of the state are brought in to make sure it doesn’t happen.
In the case of a ticket for 20 km/h over the limit on a highway, the real reason is one of revenue. This isn’t necessarily a bad thing, but the way that this tax is being applied brings about some irrational consequences.
What we have currently is a “speed limit” (as posted on signs—usually 100 km/h on the highway) and then an actual limit (as enforced by police—usually 150 km/h on the highway). For speeds at or below the “speed limit” (as posted), the highway is free to use. For all the speeds between the posted an the enforced limit, there’s a non-zero chance that you will be required to pay a fee to use the highway at that speed. The chance that you will be required to pay the fee increases with the amount of time that you are driving above the “speed limit” (as posted), and the amount of the fee increases with how much faster than the “speed limit” you are driving.
This is essentially a pay-as-you-use tax applied to drivers who want to exceed the speed limit, but instead of applying the tax equally among the community of drivers, we use a lottery—a random number generator (the distribution of traffic police in space and time) to decide who will pay.
So if v is your speed when caught by the police and t is the number of minutes you are speeding, let us take p(t) to be the probability that you will be caught speeding by the police (p is a function of time), and f(v) is the amount of the fine that you will pay (f is a function of your speed when caught). So if you are rational, you can expect to pay p(t)∙f(v) dollars for speeding at speed v for t minutes.
Unfortunately, people don’t expect to pay that much. Humans aren’t rational. They blame it on bad luck when they get caught, and they chalk it up to their own cleverness when they get away with it. Everyone wants (and expects) to be the lucky one who gets away with not paying anything.
It is the fact that this tax is applied in a probabilistic way that makes people act irrationally. Have you ever noticed that traffic slows down considerably when drivers see a traffic cop on the side of the road? There is no reason for that. By the time you see the police officer, it’s already over. He knows how fast you’ve been going, and if he’s going to radio his partner to pull you over, slowing down won’t help you out at this point.
This randomised way of distributing taxes brings in a number of other inefficiencies too. I don’t have any data to back this up, but I think it has a negative impact on our attitudes toward law enforcement. On being caught speeding by a traffic officer, who among us hasn’t thought, Don’t you have something better to do? It is also, I think, a poor use of a police officer’s time to have them standing on the side of the road with a device for measuring the speed of passing vehicles and a radio.
There are already a few technologies that exist today that could combine to solve all of these inefficiencies and irrational behaviours.
There are relatively cheap GPS machines that can indicate what the speed limit is in any given stretch of highway with very high accuracy. There are also governors—machines that regulate the speed at which a vehicle can drive, regardless of the preferences of the driver.
I propose that instead of using the “who’s gonna get caught by the police?” lottery to decide who pays the “driving over the posted limit” tax, we could use a GPS/governor system to limit and tax the use of highways at speeds greater than the posted limit.
First off, a GPS/governor system could actually enforce strict speed limits where we want them. For example, we do not want drivers to be able to drive more than 150 km/h on the highway under any circumstances. As a society, we’ve made that clear in the laws that we’ve enacted. A GPS/governor could actually prevent a car from accelerating beyond that speed. Or in the city, a GPS/governor could strictly prevent going over 30 km/h in a school zone. It would not be a matter of punishing offenders—the technology just would not allow for breaking the rules.
Then, in cases where we have already decided that we do want to allow for a certain amount of speeding, but we want to tax it, like in the case of a car travelling at 120 km/h on the highway, a GPS/governor could record the time that the driver is over the limit, and by how much. The area under that function would be the fine, and you could make that to be equal to what one would rationally expect to pay under the current system, if one was caught exactly as much as one would expect to be. So, if you are speeding for t minutes at speed v, at the end of the month, you would receive a bill from the Ministry of Transportation for exactly p(t)∙f(v) dollars. You’ll note that it’s the same amount that a rational person speeding exactly the same amount should expect to pay under the current system.
Such a system would free traffic officers to be watching for actually dangerous driving practices (texting while driving, extremely aggressive driving, etc.), and it would save money in the long run.
The difference is that all the people who think that it’s their own cleverness that has allowed them to get away with speeding will hate a system like the one I’m suggesting.