Too fast too spurious: Quinn vetoes speed limit increase

Too fast too spurious: Quinn vetoes speed limit increase

When it comes to Illinoisans and their cars, Gov. Pat Quinn can’t seem to make up his mind. This time last year, Quinn signed legislation upping the speed limit on rural interstates to 70 mph from 65 mph. He cited a fear that if Illinois didn’t keep up with higher speed limits in other states,...

When it comes to Illinoisans and their cars, Gov. Pat Quinn can’t seem to make up his mind.

This time last year, Quinn signed legislation upping the speed limit on rural interstates to 70 mph from 65 mph. He cited a fear that if Illinois didn’t keep up with higher speed limits in other states, commerce could be adversely affected. (Thirty-four states have raised speed limits to 70 mph or higher on some roads since 1995, according to the Chicago Tribune.)

But that consideration was conspicuously absent this week, as Quinn vetoed a bill that would have raised speed limits to 70 mph on all Illinois tollways. This time, he cited safety concerns.

Both speed-limit bills were extraordinarily popular, passing with veto-proof majorities in the Illinois House and Senate. This makes it very likely that lawmakers will override Quinn’s veto come November.

So what changed?

The data certainly didn’t.

As the Chicago Tribune points out, the debate over the effects of raising the speed limit is far from settled.

But treating the limit like a bona fide safety tool seems misguided.

It’s not speed itself, but rather differences in speed that cause most accidents. So when considering a limit, lawmakers must take into account how fast most drivers already drive – not how fast they’d like them to drive.

This is why the predominant rule of thumb for setting a speed limit is known as the “85th percentile speed.” It dictates that the limit should be set at a speed under which 85 percent of drivers are traveling, rounded up to the nearest 5 mph increment.

So if Quinn was really interested in driver safety, he could take a look at this handy Tribune graphic showing the 85th percentile speed on the tollways surrounding Chicago. It’s not hard to see that the limit should be raised to 70 mph, at least. If Quinn wanted the follow the rule to a T, he should actually be advocating for a 75 mph limit.

With an increase in freeway speed limits, most studies show that total accidents decrease or remain constant while fatal accidents increase. The latter is where the argument to keep speed limits lower hangs its hat – but as writer Katy Waldman pointed out in Slate, it’s difficult to tell if the spike is merely due to increased traffic volume on the newly speedy routes. Waldman wrote:

“Overwhelmingly, studies show that freeway deaths increase with freeway speed limits, although it’s hard to know how much of that upturn stems from the greater volume of overall traffic that’s drawn in by looser speed regulations.”

Addressing those who think lower speed limits will tamp down speed, she added:

“In fact, studies show that drivers rarely overshoot their speed comfort zones, even with legal encouragement—and that the perception of hazard on freeways with high speed limits can actually boost safety by heightening drivers’ caution.”

So while it may seem counterintuitive to say so, the “speed kills” argument as applied by Quinn is disputable at best. At worst, it’s an ill-considered justification for feel-good paternalism.

So the question remains: what has changed since Quinn approved higher speeds last year? The answer could be politics.

As the Tribune noted, when Quinn signed the speed-limit law on his desk last year, legislators were irritated with the governor. He had recently withheld their pay for failing to deal with the state’s pension crisis – a highly political move all its own.

But now, instead of fear, the motivating factor behind Quinn’s recent veto may be to take a “pro-safety” stance before election season.

This fresh concern appears to trump the will of the people and solid evidence supporting a relaxed speed limit across the state.

Photo credit: Chuck Berman / Chicago Tribune

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