Some states and countries have specific rules that regulate the conditions under which a motorist may enter and use a bicycle lane. Florida does not, except for a single provision in section 316.1945(1)(b), F.S., that prohibits standing or parking a vehicle “on an exclusive bicycle lane”. “Exclusive bicycle lane” is not defined, nor is “Bicycle lane”. In absence of a statutory definition, a Florida court that needed to determine whether a bike lane was present would likely consult the definition in the Manual on Uniform Traffic Control Devices, which refers to “preferential or exclusive use by bicyclists” so as to accommodate the range of state traffic regulations in the US (definition in the 2009 edition can be found at http://mutcd.fhwa.dot.gov/htm/2009/part1/part1a.htm#section1A13 ; the wording is very similar to that quoted on the Florida Bicycle Law website).

Moreover, despite its reference to “exclusive bicycle lane”, section 316.1945(1)(a), which also lists locations where a vehicle may not be stopped, does not include a bicycle lane in that list. In view of this situation, the FDOT Plans Preparation Manual definition of “Bicycle lane” refers to “preferential use” by cyclists.

In the absence of specific state regulations for bicycle lanes (other than the single one mentioned), motorist use of bicycle lanes is governed by general road rules. Thus, if a motorist entered a bicycle lane and struck a cyclist, police might presumably cite the motorist for violation of s. 316.084 (“…The driver of a vehicle may overtake and pass another vehicle on the right only under conditions permitting such movement in safety”) and/or of s. 316.085 (“…No vehicle shall be driven from a direct course in any lane on any highway until the driver has determined that the vehicle is not being approached or passed by any other vehicle in the lane or on the side to which the driver desires to move and that the move can be made with safety and without interfering with the safe operation of any vehicle approaching from the same direction”). These are standard road rules, in the codes of most states, and both of these rules are quoted on the Florida Bicycle Law page.

Re safety of passing a vehicle on the right:

There have been cases in which motorists passing other vehicles on the right struck cyclists, although I don’t recall any cases in which the cyclists were in bicycle lanes. In the crashes I heard about, a large vehicle (heavy truck or bus) had stopped in the inside (left) lane on a 4-lane roadway to make a left turn; a driver behind the stopped vehicle then entered the outside traffic lane to pass the stopped vehicle and hit a cyclist whom he had not noticed (perhaps because he hadn’t noticed cyclist as he approached the stopped vehicle, and his view of cyclist in the last seconds before he entered the outside lane had been blocked by the large vehicle).

A motorist should not use a bicycle lane to pass another vehicle if there isn’t “plenty of room” or if he can’t be sure there are “no cyclists anywhere near”. A motorist should never assume that, if they happen not to see any cyclist in a bike lane at the moment, no cyclist could be in the bike lane; determining whether an adjacent lane is clear requires making a clear, complete scan of the lane.