Magic Car Hypothetical

Okay, here’s the situation. Every car has a magic device on board which regulates how fast it can go. The only cars which are exempt are emergency vehicles. Everyone else, without exception, has a car with a magic device which regulates how fast it can go. The way the device works is that it knows (by magic) the speed limit for every street in America. Once it’s on a street, it instantly recalibrates so you can’t exceed the speed limit on that street.

For example, if you’re on a street which has a maximum speed limit of 15mph (maybe there’s a school on it or something) then, no matter what, you won’t be able to go above 15mph while you’re on that street. If the next street you go on has a speed limit of 30mph, you won’t be able to exceed that and so on.

It doesn’t matter how the device works (it’s magic), or how it knows what the speed limits are (more magic), and there’s no way to disable it or get around it. Legislators aren’t going to do anything to change the speed limits and fighting hypotheticals is punishable by death.

My question is, do you think such an arrangement would be better or worse than what we have at the moment and why?

P.S. - Motorbikes don’t exist. Don’t ask why. They just don’t.

Once my neighbor drank a bottle of rat poison and I rushed her to hospital. I broke the speed limit. Wrong?

The rate of traffic deaths has been falling steadily in the U.S. If excessive speed is a big problem, surely the very high fines in some jurisdictions are a big disincentive. What problem are you trying to solve?

No, because speeding isn’t really relevant to traffic safety, merely a tool for city governments to use police officers as tax collectors. You want to improve safety on the road, come up with a “magic” car which will shove a cell phone up the driver’s ass if he/she looks at it while the car is in motion.

I’m fairly certain that roughly 95%* of the unsafe driving I see during daily driving has nothing to do with people driving too fast. Unpredictable driving is a far, far greater danger to others on the road. So while I can’t say that it would be worse to have such a restriction imposed, I’m not sure it would be an improvement.

*Data Source: my ass.

With built-in navigation systems and electronic throttle control, modern cars already have the hardware needed to implement this; it’d just be a few lines of code needed for the car to query a central datebase and retrieve speed limits for its neighborhood, and then govern the throttle to keep the car under the limit for whatever street it’s on.

And I don’t think it’ll help much. An extra 5-10 MPH of speed is rarely the cause of an accident. Moreover, anyone who agrees with the concept of risk homeostasis would predict that implementing this safety measure may result in people changing other aspects of their driving behavior to restore the level of perceived risk that they have always been comfortable with - the result being that whatever benefit you might expect by preventing anyone from speeding might not be realized.

If all cars under this magical control then why have speed limits? Why wouldn’t the magical system make all cars go the safest practical speed for the road conditions?

I believe you’ve written the very definition of a speed limit. We’re just discussing different ways of enforcing it: whereas the current method involves penalties for exceeding the local limit, the OP’s scenario involves a system that actively prevents a car from exceeding the local limit.

A speed limit may change with conditions, but it’s still a speed limit. Near some local schools, the speed limit sign is a light board that displays a different speed limit at different times of the day, depending on whether students are commuting (lower speed limit) or are safely at school/home (higher speed limit). In either case, the top of the sign has big letters that say “SPEED LIMIT”.

Some time back I remember reading something about slow / less powerful cars being MORE dangerous on the roads

The basic reasoning was that because they are slow to accelerate, they encourage people to drive faster through corners, intersections or other “dangerous places” than they otherwise would.

I wonder if this “magic” device would have a similar effect - that people would be “encouraged” to always be going as fast as the car would allow instead of adjusting to the actual situation presented?

Counter intuitively, such a device may well raise the overall accident rate

I always thought that the definition of speed limit was
“the fastest permissable (safe) speed for a particular road under good road and weather conditions”
Where I learnt this was a “hard” (objective) number that was also supplemented by a second subjective limit that read along the lines of “you cannot drive at a faster speed than is safe for your vehicle and the conditions” -
So while a road may well have a limit of 35mph, it is not necessarily always safe to drive that fast.

If the “safest practical speed for the road conditions” is externally imposed - whether it’s by a sign/fines, or by an automated electronic throttle control system - how is that not a speed limit?

I’m going with no difference. It’s not that it’s no difference exactly, but I think the issues would net out.

There are some traffic accidents that result from excessive speed - or it is at least a contributor to the accident. Speed limiters would also prevent high speed car chases.

On the other hand, there are some times you justifiably need to go a little faster. Mountain road passing lanes come to mind - if you’re stuck behind an RV going 45, passing them at 55 is not going to cut it. You need to punch it up to 70 to pass them before you run out of road to do it.

I don’t linke it. In practice motorway limits are more suggestions than any realistic maximum and keeping everybody to the limit would not be a good thing. Especially in cases like septimus mentioned. At the very least any such hypothetical car should have an “emergency override” that any use of you have to explain to the authorities later, but is there.

I think he means it’s not a STATIC speed limit. Right now, this system would lock me at 55mph on a 2 lane highway during a blizzard, at night, following a zombie apocalypse; it would also lock me at 55mph in broad daylight when on a clear day with no other cars around.

A much more useful system would let me go 90 if I wasn’t going to be putting anyone else in danger, and then force me to slow to 35 when there was a traffic jam over the next hill.

To the OP: Strictly enforcing the speed limits we have now would suck and I won’t stand for it.

Right. There wouldn’t be a posted speed limit sign as there is now. The driver wouldn’t even know what the current limit under the conditions would be.

However, for any road there will be an absolute speed limit that may be higher than the posted speed limits we have now under ideal conditions. The absolute limits may not be much higher for common drivers, but you’d have a higher limit for emergency situations. Even that higher limit would still account for the current conditions.

So, to save one life, you’ll sacrifice dozens of others. Wrong.

Er…um…isn’t it at all possible that he put no one in danger when he exceeded the posted speed limit?

I’m not sure if I can recall, but it’s possible, just maybe, now and then, that I exceeded a posted speed limit. Not saying it happened for sure, but there’s outside chance… oh the hell with it, I speed any time it’s safe and I don’t think I’ll get caught. Speeding to the hospital because someone swallowed a bottle of rat poison (really? a whole bottle?) doesn’t have to involve putting others in danger.

No. If the speed limit was 60 on a two lame road, there would be a long line of cars behind the guy going 59. or even 55, it would take too much highway to get around him safely in the face of oncoming traffic.

It doesn’t even need to be a two-lane road. Multi-lane highways work much, much better if people speed up a bit in order to pass in a timely manner (and then get back into the right lane.) Otherwise you get the situation where traffic backs up behind a slow vehicle being passed by an only-slightly-less slow vehicle, which results in clumps of traffic driving close together despite wide swaths of empty highway nobody can get to.

Sure. And lots of people smoke cigarettes their whole lives with no adverse health consequences.

Rules and laws have to be based on averages and expectations. If there are a large number of accidents along a particular section of a street, one of the usual responses it to put up speed limit signs. Sometimes, these actually result in fewer accidents. It’s a statistical thing.

Are you from Europe? Oh wait, San Diego. Even worse… :smiley:

Rules and laws have to be based more on principles and ethics. And in America personal freedom and rugged individualism count way more than statistics. Even if that means we’ll never achieve a glorious social(-ist) utopia.