[choeger]

The same holds for a lot of other rules, from public transportation tickets over legal fireworks and drinking age to softer drugs and taxes. Society as a whole seems to be generally fine with smaller infractions and I consider this a good thing, tbh. I would be perfectly fine with a similar scheme for traffic laws.

The thing with speeding cameras is that they could easily be adjusted to allow for 20% (say at most 20kph) margin (which would be perfectly fine for me even on the German Autobahn), but drivers would learn that fact and adjust perfectly to just 1kph below that limit. This would then enrage puritans that would DEMAND that these MURDERES be PUNISHED. Sadly for some reason traffic law is an area of zero tolerance for some.

[dodobirdlord]

Unsafe driving is a real cause of a substantial amount of death, and unlike most causes of death it is not over represented in the elderly, giving it a massively outsized impact in terms of reduction in expected years of life. Motor vehicle collisions are reliably the leading cause of death of teenagers and young adults in many parts of the world. People are bad at appraising events that are rare with high negative impact, so most people, who have never experienced the consequences of unsafe (or drunk) driving consider it a minor issue.

[choeger]

Unsafe driving is not characterized by speeding a slight margin over the limit on good roads (see German Autobahn for statistics, these are among the safest roads on the planet). Similarly, I am pretty certain that driving 40 in a 30 zone (when 30 is safely possible) is not the cause of most, if any, deaths. Causes are varied, but generally the situations where one or two meters of road would make a difference are obviously rare.

So to emphasize my point: Permanent and ubiquitous speed control is the wet dream of many people, but it's a proxy. These people have a problem with cars. And there are many places where that is absolutely justified (dense inner cities for example, or streets in front of schools).

[Symbiote]

The increase in stopping distance from 30km/h to 40km/h is significant, more than 1-2 metres, and much of it is thinking/reacting time, i.e. still travelling at 40km/h. People are much more likely to survive an accident at a lower speed.

"The results from one of these studies is presented in figure 1, which shows a fatality risk of 1.5% at 20 mph [32km/h] versus 8% at 30 mph [48km/h]." [1] (in typically British fashion, the actual data is in km/h, but this general-public version of the document is presented with miles.)

The difference is even greater at the next gap (30mph→40mph, or 48km/h→64km/h). That was the subject of a road safety video a few years ago: [2]

[1] https://www.rospa.com/rospaweb/docs/advice-services/road-saf...

[2] https://www.youtube.com/watch?v=HeUX6LABCEA

[choeger]

Your source speaks of impact speed.

To achieve a difference in impact speed of 16kph, you would either have to go much faster, say 60 to 70kph before the accident or not brake at all.

There are of course situations where a driver cannot brake at all, but there the speed limit should be 10kph or less (and then going, say, 12, would again be more or the same).

On a road where 30kph is considered safe, 40kph is only slightly less safe.

[hannob]

I live in a city where 48 people were killed by cars last year. I am not fine with that.

[choeger]

Don't get me wrong, you shouldn't. But how many of these deaths would have been prevented by a 20% less speed?

[andor]

That's a rather distasteful argument to make and reminds me of Covid deniers blaming underlying medical conditions for deaths.

Kinetic energy is m*v^2, so yes 20% makes quite a difference.

Also, what's the point of a speed limit of x if 1.2x (or x+19) is tolerated. There is no good reason for a margin.

[choeger]

Oh, come on. First of all, speed limits are chosen conservative for various conditions. Second, cars are usually better than expected. And finally, every rule has margins (see my examples above). There is no reason to consider speed limits special.