Actually, the law is not "fair" at .08.
As part of some editor's plea bargain no doubt (my darkly suspicious supposition), Car & Driver ran a story about 15 years ago about drunk driving that keyed on an actual test of three male editors on a closed track (Chrysler Corporation's) administered by Michigan state police, who served as technicians, course observers, safety officers, and barkeepers.
If you read the article at the top of the thread, the author tells us that the old standard initially erected by the American Medical Association 60-odd years ago was 0.15% BAC, as a reasonable "approximate" mean or median (mean and median are NOT the same, btw) number LE could hang their hat on, in trying to frame a "fair" standard.
And lo and behold, the graphical data resulting from Car & Driver's drunken-driving skills test actually suggests that the AMA was right the first time.
Looking at driver responses at rising BAC levels over time, these three very experienced and knowledgable drivers seemed to me to have been essentially unimpaired up to about 0.16% BAC, and even arguably capable of safe navigation a little higher than that, although by 0.22% they were all clearly doing a bad job of driving, and I wouldn't trust myself to ride with even a Terry LaBonte or an Innes Ireland if he'd had that much to drink. (The case of Princess Diana and Dodi Fayed's late driver, Mr. Paul, comes to mind.)
The other points raised by the author are all likewise cautionary. The three C&D editors were all youngish guys of average build and weight. A woman editor standing 5'3" and neatly filling out a sightly size-4 business suit would display a radically different inebriation curve, as would a Green Bay lineman in Olympic-champion physical condition. (And if the lineman took his drinks while actually playing a game and huffing oxygen with big hits of Gatorade while sitting down, he might not even become inebriated at all, if you think about it.)
Reminds me of an educational visit the Honolulu Police Department had onboard my submarine, complete with graphic slide shows.
What stuck right out to me was when the officers mentioned that traditional field sobriety tests do not work well on the average military person because they are more coordinated and have faster reaction time than the average citizen.
I began to wonder how circular the logic could get. You must not drive after consuming alcohol because it impairs your abilities, but since your abilities are not impaired, we must arrest you simply for driving after consuming alcohol.
Excellent post.