According to 2 Fast 4 Safety?, higher speed limits don’t lead to more death — among young to middle-aged men:
[A]ccording to a recent academic study, raising speed limits to 70 miles per hour, and even higher, has no effect whatsoever on the death rates of young and middle-aged male drivers.
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Like most studies that seem to grant us leave to indulge our lazy, bad habits, this one comes with an asterisk, unfortunately, that it would be cruel not to disclose (despite the fact that as a young male Westerner I’d love to bury the finding in a footnote): higher speed limits do increase the death rates of women and the elderly. The scientists can’t agree on the reason for this discrepancy, and if they’re wise they won’t try, lest they end up confirming the prejudices of people like my old high-school buddy who cursed every time a female driver of any age had the nerve to appear in the mirrors of his Chevy Nova.
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A few years ago in Montana, my home state, there was no posted speed limit on highways, just a vague rule about driving in a ”reasonable and prudent” manner. This haziness forced motorists to think, adjusting their speeds according to the conditions while hoping that lurking state troopers agreed with them. I felt flattered by this invitation to use my judgment and drove more consciously than I ever had. I felt like a grown-up. Then they changed the law, instituting a top limit of 75 m.p.h. Suddenly, I was a rebellious child again. Whether it was day or night, raining or sunny, I treated 75 as a new minimum — as the opening bid in a floating poker game.Seventy-five, you say? I’ll raise you four. No sirens yet? I’ll raise you six.
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A friend of mine, Ross, a former Navy pilot who regularly drives between Phoenix and Seattle by way of empty Nevada, argues persuasively that velocity isn’t as treacherous as it’s said to be; the real risk is variations in velocity. ”When you’re in the Navy flying formation at 350 knots” he says, ”everybody’s fine, but if one guy’s going 340, you’ve got a problem.” For Ross — and I’ve heard of experts who agree with him — unrealistically low speed limits widen the gap between law-abiding slowpokes and the restless majority, resulting in lots of risky passing maneuvers and general chaos.