Comment by minikites | Hacker News Reader

Comment by minikites | Hacker News Reader

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We do ask people to guess whether or not they are committing DWI/DUI though, which is a huge problem in my opinion. Cockeyed.com sums it up better than I can:

http://www.cockeyed.com/science/breathalyzer/breathalyser01....

> Monitoring blood alcohol levels is difficult. Holding people accountable for crossing the .08 limit is like holding them accountable for trespassing once they walk past a particular longitude. The line is invisible. It is possible to determine your longitude, but it is awfully tricky if you don't own a sextant or GPS unit.

> Imagine if cars did not have speedometers, but speeding laws were still enforced with $2,000 police radar guns. It would be really difficult to tell how fast you were going, particularly (as is the case with blood alcohol levels), you had never experienced having your speed tested, nor had any real experience with what a particular speed (for example 55 mph) feels like.

There's two ways to ensure that you aren't inadvertently running afoul of drinking and driving laws: you can either not drink, or wait a large amount of time after drinking before you drive.

Same with passing bicycles - you can give them so much more than three feet that there's no chance that you're within three feet of them, or not pass them until there is that much room.

Three feet is the minimum. The expectation isn't that drivers should try to get as close to three feet without going over.

Should we treat speed limits the same way, so everyone drives around at a crawling pace?

You could do that. But most cars come with a handy dashboard-mounted speed indicator device, often in plain view of the driver - so you could use that to determine your car's speed instead.

You should, uh, read the whole thread, it's an analogy.

The comparison doesn't strike me as a very good one. There are no good, quick, easy ways of measuring how far from a cyclist you will be when you pass them, or your blood alcohol content (which is anyway only a crude proxy for level of intoxication, and besides is commonly measured by alcohol in one's breath, which isn't quite the same thing). That's why people are advised to err on the side of caution.

When it comes to speed, on the other hand, every car comes with a speedometer. Erring on the side of caution would not be a crime (the speed limit is a limit, after all, not a goal...), but it's far less necessary.

It's a pretty crappy analogy.

Would make everybody safer.

What's the problem with using a breathalyzer? Seems like a good investment if you want to drive after drinking often.

France mandated breathalyzer kits in all cars a few years ago, although it has since been suspended[1].

[1] http://www.thelocal.fr/20130124/france-motorists-drivers-sus...

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