The GAO put out a fascinating report on drunk driving, which contained this interesting statement: "Overall, the evidence does not conclusively establish that .08 BAC laws, by themselves, result in reductions in the number and severity of alcohol-related crashes." That's a long-winded way of saying that the .08 that'll get you a DUI isn't even unusually dangerous.
For decades, the DUI limit for was .10. The BAC limit was lowered to .08 in the 80's and 90's. Thus, there should have been a decline in drinking-related deaths. Yet there wasn't. Thus, the .08 BAC is an arbitrary scam number designed to increase the number of tickets issued - and thus revenue collected.
It's also very easy to blow a .08:
On average, according to NHTSA, a 170-pound man reaches .08 BAC after consuming five 12-ounce beers (4.5-percent alcohol by volume) over a 2-hour period. A 120-pound woman reaches the same level after consuming three beers over the same period.
A 4.5% beer is Miller Lite. The stuff I drink is always in the 6-9% range, as I only drink IPA's or artisan beers. It's easy to drink five beers in two hours, and even easier to drink 2-3.
Your liver only "clears" 1-2 beers an hour. That is, if you drank five beers in two hours, you'd still blow a .08 if you then paced yourself at a one-beer-an-hour rate.
It gets even more complicated when ordering mixed drinks. "One 12-ounce beer has about the same amount of alcohol as one 5-ounce glass of wine, or 1.5-ounce shot of liquor." How strong is each drink? How many ounces of gin are in that G&T? How can you ever safely drive after a couple of drinks?
What's worse is that breathlyzers are unreliable. Even if you're not "drunk" under the law, the pseudo-scientific breathalyzer may still have you blowing a .08.
Even if you're over 170 pounds (who in America isn't?), those averages work out. BAC is a measure of alcohol relative to body hydration. Even 30 extra pounds of fat doesn't increase hydration, as very little water is stored in fat tissue.
A DUI, on average, costs $10,000:
If you need any more reasons not to drink and drive, consider this: A driving-under-the-influence conviction is a financial wrecking ball. A typical DUI costs about $10,000 by the time you pay bail, fines, fees and insurance, even if you didn't hit anything or hurt anybody.
That number is low for two reasons. First, the lawyer I'd hire if charged with a DUI charges $10,000. That's just the legal fee. Second, that number doesn't calculate the hundreds of hours of lost work from having to perform community service. If $10,000 is sticker shock, imagine how you'll fee when the numbers are greater.
When in doubt, take a cab. Consider it DUI insurance. Even if you leave your car and it gets towed, the $250 will be much cheaper than the cost of a DUI. Also, many cab drivers know people who will drive your car home for you. In Los Angeles, there was a cabbie who'd drive around with a bike the trunk of his car. If it wasn't too far away: He'd toss the bike in your trunk, drive you home, and then bike it back to his cab. He only charged $100. Ask around.
In the real world, most of us are going to drive after a drink or two. How can you be safe on the road while also avoiding a DUI? My rule is simple: One mixed drink per hour. If I drink two G&T's in an hour, I won't drive for another hour (i.e., two hours total). Instead, I'll start drinking water. If I leave the bar, I'll go for a walk. Whatever the case, I never average more than one drink per hour.
Driving after even a single drink puts one at risk for a DUI. It's better to take a cab or walk. Barring that, only drink at one location, and save your receipt. That way, if stopped and given a false DUI, you'll have at least some record of your alcohol consumption - perhaps enough for your $10,000 lawyer to raise reasonable doubt.
End of Public Service Announcement.
(BTW, I'm closing comments because this useful post is exactly the type to attract spammers and self-promoters.)