Bicycles are not motor vehicles, and why it matters
Actually, we should have said: riders of bicycles are not bound by rules that apply only to drivers of motor vehicles…
It’s helpful to note that the “rules of the road” apply not to vehicles, or bikes, but rather to the people operating these things. A typical example is the rule for what to do at a stop sign, §28-855(B). “A driver of a vehicle approaching a stop sign shall stop…”.
In Arizona, bicycles are, by definition, not vehicles; nor are they motor vehicles. Here are those definitions §28-101:
§28-101. Definitions ... 58. "Vehicle" means a device in, on or by which a person or property is or may be transported or drawn on a public highway, excluding devices moved by human power or used exclusively on stationary rails or tracks. 33. "Motor vehicle": (a) Means either: (i) A self-propelled vehicle. (ii) For the purposes of the laws relating to the imposition of a tax on motor vehicle fuel, a vehicle that is operated on the highways of this state and that is propelled by the use of motor vehicle fuel. (b) Does not include a motorized wheelchair, an electric personal assistive mobility device or a motorized skateboard...
So, if a bicycle is not a vehicle, why does a cyclist have to stop at stop signs? Simple, because of a law helpfully titled Applicability of traffic laws to bicycle riders, §28-812,
§28-812. Applicability of traffic laws to bicycle riders A person riding a bicycle on a roadway or on a shoulder adjoining a roadway is granted all of the rights and is subject to all of the duties applicable to the driver of a vehicle by this chapter and chapters 4 and 5 of this title, except special rules in this article and except provisions of this chapter and chapter 4 and 5 of this title that by their nature can have no application.
This is a cyclist’s fundamental right to the road; the equal of driver’s.
Note well that it refers specifically to the rights and duties of the driver of vehicle — and NOT the driver of MOTOR vehicle, in fact the word motor does not appear at all in 28-812.
It might surprise you to note that the phrase “motor vehicle” occurs only a handful of places in ARS Title 28, Transportation, with respect to how a driver must operate a vehicle. By far, most driver’s duties refer, as in the stop sign example above, simply to vehicle.
Some references are incidental; lane and speed restrictions on motor vehicles weighing over 26,000 pounds (§28-736, §28-709). Another was intended to set minimum passing clearance when a motor vehicle overtakes a bicycle (§28-735). Two germane examples for cyclists are following distance, and impeding traffic.
§28-730, “The driver of a motor vehicle shall not follow another vehicle more closely than is reasonable and prudent…”, without the word motor in this statute, pacelining would likely be illegal. Since reasonable people would probably agree that a couple of inches is an inappropriately small following distance.
§28-704(A), “A person shall not drive a motor vehicle at such a slow speed as to impede or block the normal and reasonable movement of traffic…”. This is what I refer to as the cyclist’s second most fundamental right to the road, because if this statute were to apply to cyclists, then they would in effect be not allowed to use any road where traffic even might be impeded; regardless of number of lanes, width, presence or absence of a bike lane, or anything else. There is some detailed minutia [see footnote 2, here] revolving around what is meant by the “normal and reasonable movement” but that is immaterial to cyclists, since this section is inapplicable to them.
Likewise, §28-701(E) “A person shall not drive a MOTOR vehicle at a speed that is less than the speed that is reasonable and prudent under existing conditions”, never applies to bicyclists.
The point is that the phrase motor vehicle is used sparingly and deliberately to apply only to drivers of that type of vehicle, reflecting clear legislative intent. In the case of 28-704(A) to allow cyclists to use all roads even though motorists might sometimes be impeded (with some caveats: There is a specific allowance for prohibiting bicycles on controlled access highways, and other roads on a case-by-case basis). And the purpose of these laws is so that bicyclists can ride both legally and safely in the road according to best practices.
Arizona is one of 42 states (and the UVC) that makes it explicit that only motor vehicle drivers are subject to the impeding law; and in any event the impeding rule as interpreted must take into account the capability of the vehicle in determining if a violation has taken place; see Trotwood v. Selz, concerning an Ohio bicyclist, and Lott v. Smith, concerning a Georgia farmer driving a combine.
this is one of an occasional series on laws governing bicycle use in Arizona

Elliot Road, eastbound east of Priest Drive, City of Tempe. Sign placed by the city reminds users to “Share the Road”. Posted speed limit 45mph. Even the fastest bicyclists will be traveling well below the posted speed limit. This arterial, like most, has lanes which are “too narrow to share safely side by side”, and as such, cyclists going straight ahead are advised to ride near the center of the right-most through lane. Motorists wishing to overtake must change lanes (at least partially) to pass legally and safely.
The official Arizona drivers license manual states has corrected the quote (it used to say “as drivers of motor vehicles”, which was misleading):
I also happily note that the term ‘accident’ was dropped from the manual sometime in the 2014 timeframe. #crashnotaccident
in 2013 there was a news story about TBAG’s excellent Every-Lane-is-a-Bike-Lane billboard; in it the Tempe Police spokesperson some bad/incorrect things but at the time I sloughed it off…
Besides being incorrect for reasons explained in this article, it’s bad because it infringes on bicyclists’ rights to use streets in the safest manner, which on many roads will of necessity impede motorists. Safety first, not convenience.
Here is how the MassBike/FHWA Law Officer’s Guide for increasing safety through traffic enforcement explains the general/generic impeding statute; slide 57 —
Lane Positioning: Impeding Traffic
– Impeding traffic rule: may apply to motor vehicles only.
– Does not prohibit use of roadway at bicycle speeds.
– Mountain roads: use turnout where there is a line of vehicles.
Q1. What is an impeding traffic statute?
A1. Here is the California version: “No person shall drive upon a highway at such a slow speed as to impede or block the normal and reasonable movement of traffic unless the reduced speed is necessary for safe operation, because of a grade, or in compliance with law.” CVC 22400. (a)
Q2. Why doesn’t this law apply to bicycles?
A2. It does not either because “the reduced speed”is normal bicycle operating speed or because the statute specifically applies to motor vehicles. When it is ambiguous, courts have said that it does not apply to bicycles using the road at ordinary bicycle speed.
Q3. What if there is a long line of traffic behind the cyclist?
A3. In those very rare circumstances where there is no opportunity to pass for a long time, a courteous cyclist might pull off the road if there is a place to do so. California is one of the few states that requires this (for all slow-moving vehicles): “On a two-lane highway where passing is unsafe because of traffic in the opposite direction or other conditions, a slow-moving vehicle, including a passenger vehicle, behind which five or more vehicles are formed in line, shall turn off the roadway at the nearest place designated as a turnout by signs erected by the authority having jurisdiction over the highway, or wherever sufficient area for a safe turnout exists, in order to permit the vehicles following it to proceed. As used in this section a slow-moving vehicle is one which is proceeding at a rate of speed less than the normal flow of traffic at the particular time and place.” CVC 21656
Interesting because it involves impeding and a google self-driven car; which apparently operates on LSV/NEV rules (restricted to a maximum speed of 25mph, and only allowed on roads posted for 35mph and below).
CA’s impeding statute has all the same provisions as AZ’s, except CA omits the word “motor” — which is irrelevant for a motorized vehicle.
On the surface, it simply looks like the Mountain View police correctly did not issue an impeding violation. But if you read deeper, it shows the deep cognitive dissonance in the minds of many law enforcement officers regarding how they zealous protect the “right” of motorists to travel as fast as they can; even though there is no such right. The MV PD staunchly insist, it would have been *correct* for the officer to issue a citation, but instead he used his discretion to not issue one. This all despite the plain exception, see e.g. this chain of comments: