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by dahdum 3015 days ago
Numerous studies have shown increased accidents with the use of red light cameras (others have shown decrease in collisions but also increase in severity). In Florida for instance, fatalities and collisions went up. [1]

Speed limits are also based in large part on the 85th percentile speed of actual traffic, which presumes 15% of drivers are breaking the law.

So no...I don't believe absolute traffic enforcement was ever envisioned, and I don't recall ever hearing of a politician running on that platform.

Lest you believe I'm a law breaker looking for leniency, in over 20 years of driving I've never received a moving violation.

[1] http://www.sun-sentinel.com/news/florida/fl-nsf-red-light-ca...

1 comments

Okay, I read that article, and it said traffic went up over 8.32% overall, and then showed some increases in accidents near 8%. It looks like they reported absolute numbers without controlling for the increase in traffic. If traffic was up 8.32%, and angle crashes were up 6.72%, doesn't that imply that angle crashes were actually reduced by around 1.6% per capita?

What about this one:

"Insurance Institute for Highway Safety study stated that fatal crashes from red light runners increased by 30 percent per capita after cities turned off their red-light camera programs."

> Speed limits are also based in large part on the 85th percentile speed of actual traffic, which presumes 15% of drivers are breaking the law.

It's a misleading assumption to suggest that the way speed limits are determined actually implies a design intent to retain a 15% minority of law breakers. The stated and explicit intent of posting the speed limit is to set the maximum, and for nobody to exceed the maximum.

Also: "The speed limit is commonly set at or below the 85th percentile operating speed (being the speed which no more than 15% of traffic is exceeding) and in the US is frequently set 4 to 8 mph (6 to 13 km/h) below that speed." (https://en.wikipedia.org/wiki/Speed_limit#Maximum_speed_limi...)

> So no...I don't believe absolute traffic enforcement was ever envisioned

It doesn't matter what was envisioned. We don't need to preserve what was envisioned.

> in over 20 years of driving I've never received a moving violation.

That's great! I would be more impressed if you hadn't done any speeding or run any red lights in 20 years. (I can't claim that, though I also haven't had any tickets in 20 years.)

A better solution would be to do regular speed studies and actually update the speed limits posted. Also, prevent municipalities from passing laws on their own speed limits and creating speed trap situations.

I see a lot of speed limits that are woefully out of date and/or very different from the 85th percentile speed on any one motorway.

> It doesn't matter what was envisioned. We don't need to preserve what was envisioned.

Then we should just ditch the whole speed limit concept. You should be punished for variance from 85th percentile speed on a motorway in either direction. Too slow or too fast are both dangerous