Educated cyclists know that they not only can (legally), but should (for safety) occupy an entire lane when conditions dictate. One of these conditions is when the lane is narrow.

Arizona law is quite strong and plain in this regard. Here is the relevant law, (I intentionally clipped the part about the cyclist’s speed, which is briefly treated later).

§28-815. Riding on roadways… A. A person riding a bicycle…shall ride as close as practicable to the right-hand curb or edge of the roadway, except… 4. If the lane in which the person is operating the bicycle is too narrow for a bicycle and a vehicle to travel safely side by side within the lane.

So this law creates a duty in part A for cyclists, but there are enumerated exceptions to this duty, the 4th one being the subject of this article.

We are reminded that from time to time, cyclists are targeted by law enforcement for “taking the lane”. This sometimes takes the form of mis-guided paternalism — “you should always ride to the extreme right so you don’t get hit”. It also can take a an uglier tone of faux-paternalism, really just a thinly-veiled automobile-superiority attitude, the sub-text being “cyclists must always get out of the way of cars”.

And disappointingly sometimes cyclists are found guilty (actually “responsible” is the correct term, I am told) by compliant lower courts.

Happily, Arizona cyclists can point to not one but two relatively recent Superior Court decisions which reversed on appeal these wrongful convictions.

The first case, Arizona V. Goren, occurred in Tempe (Maricopa County). In the second case the rider was riding two abreast, but that isn’t relevant to the case; Arizona V. Piscopo, Pima County (see more generally at Two Abreastness. Also see the case at TBL, the blog of the lawyer who represented Piscopo).

I would encourage everyone to read both of these decisions because they are brief, well-written, and illustrative.

How narrow is narrow?

This can be a gray area; it is not (directly) specified in the law. In Goren, Officer Robinson maintained that 12’10″ (his measurement) was more than ample. He was, however, not aware of the concept of usable space; and thus incorrectly counted the gutter as lane width. In the end, the court accepted that the defendant’s measurement approximately 11′ usable width was both accurate and clearly narrow. Much the same conclusion was reached in Piscopo: “credibility was not at issue and the salient evidence — the dimensions at play — appear undisputed”, the dimension according to the defendant were “no more than 11 feet wide”.

Both cases counted on using the minimum 3′ passing distance specified in §28-735 as an entitlement to the cyclist when determining narrowness. (see Three-Foot Laws for more generally about this law including other states who have a passing-distance law)

From an engineering perspective, the authoritative AAHSTO Guide for the Development of Bicycle Facilities, 1999 says minimum 14′ usable width for side-by-side sharing:

In general, 4.2 m (14 feet) of usable lane width is the recommended width for shared use in a wide curb lane…(the gutter pan should not be included as usable width).

You can play with the dimensions, e.g. if you allow a minimum of 1 foot both to the left of the (8′) motor vehicle, and the right of the (2′) cyclist, plus mandated 3′ between the cyclist and motor vehicle — you come up with something akin to the 14′ mentioned by AAHSTO. Many vehicles are less than 8′, but not by much — and don’t forget to include the mirror width which is commonly not included in specifications. Traffic engineer and cyclist Richard Moeur has created an elegant schematic drawing divvying up the 14′ here.

The Issue of Speed

Neither of the aforementioned cases dealt with whether or not the cyclists were “at less than the normal speed of traffic”. In a nutshell: some courts (but none in Arizona, that i know of) have held that normal means normal for a bicycle. See e.g. State V Patrick , which references the Selz decision; both out of Ohio.

But what about Impeding?

This was not at issue in either of these cases, for some more general discussion of impeding see Bicycles are not Motor Vehicles and Why it Matters.

The Pima County Sheriff’s Office

There is a memo from Lt. K. Woolridge date March 5, 2009 which states the (Pima) county attoney’s position particularly with respect to riding two-abreast. Further inquiries are directed to Seargent Copfer.

Thinking of Representing Yourself?

There are a number of guides for pro se / pro per appellants on the Arizona Supreme Court website.

In the commentary there, someone pointed out a link to an interesting Mionske blog/article regarding the quandary over obeying baseless orders of law enforcement.

But, back to Arizona — to recap the impeding stuff, it is important to know that Bicycles are not motor vehicles…, to understand Arizona’s general-purpose impeding statute does not apply to cyclists.

And for some general references see Two abreastness.

§28-815 B. Persons riding bicycles upon a roadway shall not ride more than two abreast except on paths or parts of roadway set aside for the exclusive use of bicycles.

Note that this statute, unlike the Wisconsin equivalent, does not have any conditions.  Wisconsin statute [346.80(3)(a)] .”Persons riding bicycles or electric personal assistive mobility devices upon a roadway may ride 2 abreast if such operation does not impede the normal and reasonable movement of traffic.”

But since Arizona cyclists are subject to all the other bicycling rules that doesn’t really matter.

Other, really hypotheoretical, arguements claim that the whole two-abreast thing is a grey area because of the stay-right rule:

§28-815 A. A person riding a bicycle on a roadway at less than the normal speed of traffic at the time and place and under the conditions then existing shall ride as close as practicable to the right-hand curb or edge of the roadway, except…

If we stipulate that none of the exceptions applies at the time, the argument goes, that the “outside” (the one further from the curb/edge)  cyclist is by definition in violation of this rule. I know of no case law on this subject, and I would conjecture that it’s unlikely there ever will be.

As a practical matter, most places where it would matter around here are urban arterials that have been built with narrow, multiple lanes. Because they are narrow; the ride-right rule, §28-815 A does not apply. Because they are multi-laned; the impeding rule,  §28-704 C does not apply (and §28-704 A only applies to motor vehicles, not all vehicles).

So, the bottom line is if you would be allowed to impede when riding single-file — e.g.  and most often because of a lane that is too narrow to share — then you may also impede two abreast.

Also note that it is always illegal to ride more than two abreast in the roadway, regardless of its impact on impeding, or anything else.

Other gray areas of abreastness: how does one cyclist pass a pair of cyclists riding two abreast? Does riding two abreast in the roadway, abreast of a third cyclist on the shoulder equate to three-abreast? What about a bicycle lane — is a bicycle lane part of the roadway?

It also occurs to me that groups of cyclists often appear from behing to be operating many-abreast when in fact (as seen from above, say) they are no more than two abreast.