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July 2018

Idaho stop?

by John Allen

There are two requirements at a stop sign: stopping, and yielding right of way. The yielding is what prevents crashes.

A so-called "Idaho stop" law allows bicyclists not to come to a full stop unless necessary for yielding. The Idaho stop gets its name because it is, in fact, the law in Idaho, and has been for a number of years. Delaware has adopted it, Colorado is allowing localities to adopt it and it is being proposed for Massachusetts too.

One common explanation for the Idaho stop is that bicyclists and motorists should have different rules. Different rules certainly do make sense in situations which relate to equipment, vehicle width, vulnerability and permissions (For example, bicycles are prohibited on limited-access highways and motor vehicles are prohibited on paths). But getting back to the question of stop signs, in reality, neither bicyclists nor motorists usually come to a full stop at stop signs unless restricted sight lines or conflicting traffic make a stop necessary.

The Idaho stop proposal reflects this reality, at least for bicyclists, but on the other hand, it is a software solution to a hardware problem which has become so entrenched that it now is also a behavior problem. The USA heavily overuses stop signs where yield signs would be sufficient, reflecting political pressure to "do something". On neighborhood streets with low speed limits, no signs really ought to be necessary, yet drivers sometimes think that they don't have to be prepared to yield, because they expect a stop sign in the cross street. Excessive use of stop signs produces a "cry wolf" situation which only calls for more stop signs, and onward to political pressure for more expensive and gaudy solutions such as flashing displays where stopping is actually needed. In Massachusetts, there is, to be sure, often no stop sign at the "vertical" leg of T intersections, but there, it is possible only to turn right or left, and that always requires a yield.

A neighborhood four-way intersection near my home used to be uncontrolled, but as of a few months ago, it got two-way stop signs. While it may be no coincidence that the Mayor drives a stop-sign-free route through this intersection on her way between her home and City Hall, she has lots of support for the stop signs. And there was in fact a nasty right-angle collision at this intersection a few years back.

A major national educational campaign would be needed to reinforce the understanding of yield signs and uncontrolled intersections which is common knowledge in, say, France, and I can't see that happening. We do have increasing use of shark's tooth yield markings in the USA, and I consider that to be a positive development.

Research has shown that Idaho stop law doesn't increase bicyclists' crash rate. And, almost all motorists, safely slow and are prepared to yield at stop signs, but the percentage who actually stop when a stop is not needed is very low, except when a driver's license examiner is looking over a candidate's shoulder. There's a cognitive dissonance in that people understand that a stop sign doesn't require a stop. Making that legal for bicyclists but not for motorists adds to the dissonance.

For now, I'm going to admit that I don't come to a complete stop unless I must in order to yield, or to make it clear that Iíll yield. Usually, slowing way down communicates that, and I can cross the intersection in less time if I donít put a foot down. Communication is, in my opinion, the important issue.

While stop sign installation often reflects politics, the requirement to yield to a vehicle which reaches an uncontrolled intersection or four-way intersection before yours rests solidly on logic. And at four-way uncontrolled intersections and four-way stops -- and even with an Idaho stop law -- you yield to a vehicle coming from the right if it arrives at nearly the same time. The logic here: you have half the width of the cross-street in which to stop, in case of any confusion.

Sometimes I do have to merge farther toward the center of the road and keep pedaling assertively, to let a motorist know that I expect a stop. Sometime I have to direct traffic like a traffic cop with hand signaling, to let a driver know that I am going to stop and stay stopped. That's the real world, folks. It is good that a bicyclist is out in the open and can do that!

Be safe out there!

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