City of Philadelphia v. New Jersey
437 U.S. 617 (1978)
New Jersey law enacted a law that prohibited most "solid or liquid waste which
originated or was collected outside the territorial limits" of New
Jersey from being imported into the State.
as well as private landfill operators in New Jersey and several cities
outside New Jersey sued on the basis that this was a ban on article of
Jersey Supreme Court upheld the law on the grounds that it, "advanced
vital health and environmental objectives with no economic discrimination
against, and with little burden upon, interstate commerce."
US Supreme Court found the law unconstitutional.
Court found the law unconstitutional because it violated the Dormant
Stewart said, "whatever New Jersey's ultimate purpose, it may not
be accomplished by discriminating against articles of commerce coming
from outside the State unless there is some reason, apart from their
origin, to treat them differently."
other words, New Jersey couldn't regulate beyond its borders.
the Court held that legitimate local interests which had incidental
interstate effects were within the State's general police powers, but
protectionist legislation per se that is enacted by the State would be
New Jersey were to buy all the landfills, and then decide to only accept
New Jersey wastes, under the market participation doctrine, that would be completely legal.