MR. JUSTICE POWELL delivered the opinion of the Court.
We consider on this appeal whether administrative regulations of the State of Wisconsin governing the length and configuration of trucks that may be operated within the State violate the Commerce Clause because they unconstitutionally burden or discriminate against interstate commerce. The three-judge District Court held that the regulations are not unconstitutional on either ground. Because we conclude that they unconstitutionally burden interstate commerce, we reverse.
Appellant Consolidated Freightways Corporation of Delaware (Consolidated), a Delaware corporation with its principal place of business in Menlo Park, Cal., also is a common carrier of general commodities by motor vehicle. Consolidated operates nationwide, providing service under a certificate of public convenience and necessity in 42 States and Canada. Among other routes, Consolidated carries commodities between Chicago, Detroit, and points east, and Minneapolis and points west to Seattle. Unlike Raymond, Consolidated does carry commodities between Wisconsin and other States, and it maintains terminals in Milwaukee and Madison where truckloads of goods are dispatched and received.
Both Raymond and Consolidated use two different kinds of trucks. One consists of a three-axle power unit (tractor) which pulls a single two-axle trailer that is 40 feet long. The overall length of such a single-trailer unit (single) is 55 feet. This unit has been used on the Nation's highways for many years and is an industry standard. The other type truck consists of a two-axle tractor which pulls a single-axle trailer to which a single-axle dolly and a second single-axle trailer are attached. Each trailer is 27 feet long, and the overall length of such a double-trailer unit (double) is 65 feet.
The double, which has come into increasing use in recent years, is thought to have certain advantages over the single for general commodities shipping. Because of these advantages, Raymond would prefer to use doubles on its route between Chicago and Minneapolis. Consolidated would prefer to use doubles on its routes between Chicago, Detroit, and points east, and Minneapolis and points west, as well as on its routes commencing and ending in Milwaukee and Madison. The most direct route for all of this traffic is over Interstate Highways 90 and 94, both of which cross Wisconsin between Illinois and Minnesota. State law allows 65-foot doubles to be operated on interstate highways and access roads in Michigan, Illinois, Minnesota, and all of the States west from Minnesota to Washington through which Interstate Highways 90 and 94 run.
Wisconsin law, however, generally does not allow trucks longer than
55 feet to be operated on highways within that State....
Appellants presented a great deal of evidence supporting their allegation that 65-foot doubles are as safe as, if not safer than, 55-foot singles when operated on limited-access, four-lane divided highways. For example, the Deputy Director of the Bureau of Motor Carrier Safety, Federal Highway Administration, United States Department of Transportation, testified on deposition that the Bureau's five-year study of the accident experience of selected motor carriers that use both types of trucks showed that doubles are safer than singles in terms of the number of accidents, injuries, and fatalities per 100,000 miles, and in terms of the amount of property damage and number of injuries and fatalities per accident. The deponent's own expert opinion was that doubles are safer because of the articulation between the first and second trailers, which allows greater maneuverability and prevents the back wheels of the second trailer from deviating from the path of the front wheels of the tractor (offtracking) as much as the back wheels of a 55-foot single; because loads typically are distributed more evenly in doubles than in singles; and because doubles typically have better braking capability than singles.
Other experts testified that 65-foot doubles brake as well as 55-foot singles, maneuver and track better, are less prone to jackknife, and produce less splash and spray to obscure the vision of drivers in following and passing vehicles. These experts agreed that the difference in the amount of time needed to pass a 55-foot single and a 65-foot double has no appreciable effect on motorist safety on limited-access, four-lane divided highways. Appellants also produced depositions and affidavits of state highway safety officials from 12 of the State where 65-foot doubles are allowed on some or all highways; all shared the opinion that 65-foot doubles are as safe as 55-foot singles....
The State, for reasons unexplained, made no effort to contradict this evidence of comparative safety with evidence of its own....The reason for the Commission's adoption of these regulations, according to the Chairman, was its belief that the people of the State did not want more vehicles over 55 feet long on the State's highways....
Appellants also produced uncontradicted evidence showing that their
operations are disrupted, their costs are raised, and their service is
slowed by the challenged regulations...On routes through Wisconsin between
Chicago and Minneapolis, both Consolidated and Raymond are compelled to
use 55-foot singles instead of 65-foot doubles because each trailer of
a double would have to be pulled by a separate tractor on the portion of
the route that is in Wisconsin. On its long east-west routes from Detroit
and Chicago to Seattle, Consolidated must divert doubles south of Wisconsin
through Missouri and Nebraska in order to avoid Wisconsin's ban....
The State replies that the general rule of Pike is not applicable to a State's regulation of motor vehicles in the promotion of safety....It is true that the Court has been most reluctant to invalidate under the Commerce Clause "`state legislation in the field of safety where the propriety of local regulation has long been recognized.'" In no field has this deference to state regulation been greater than that of highway safety regulation.
Despite the strength of this presumption, we are persuaded by the record in this case that the challenged regulations unconstitutionally burden interstate commerce. As we have shown, appellants produced a massive array of evidence to disprove the State's assertion that the regulations make some contribution to highway safety. The State, for its part, virtually defaulted in its defense of the regulations as a safety measure....
Moreover, appellants demonstrated, again without contradiction, that
the regulations impose a substantial burden on the interstate movement
Exploring Constitutional Conflicts