The U.S. Supreme Court case Askew v. American Waterways Operators, Inc., 1972 revolved around a Florida law that required owners of oil-carrying vessels to demonstrate financial responsibility up to $1 million in the event of an oil spill or other environmental damage caused by their operations. The American Waterways Operators, along with several other maritime and insurance industry groups, challenged this law on the grounds that it was preempted by federal laws regulating interstate commerce and maritime activities. However, the Supreme Court upheld Florida's statute in a unanimous decision (with two justices not participating). The court found that while Congress had enacted legislation addressing water pollution from ships, it did not intend to occupy the field so completely as to preclude states from supplementing those standards with additional requirements for vessels operating within their waters.

In the dissenting opinion for Askew v. American Waterways Operators, Inc., Justice Rehnquist argued that Florida's Oil Spill Prevention and Pollution Control Act did not conflict with federal law. He believed that the state had a legitimate interest in protecting its waterways from oil pollution and should be able to enforce stricter regulations than those set by federal standards if it chose to do so. Furthermore, he contended that Congress did not intend to preempt all state regulation of oil spills when it passed the Federal Water Pollution Control Act Amendments of 1972 but rather sought cooperation between states and the federal government in preventing water pollution. Therefore, he disagreed with the majority's ruling striking down parts of Florida’s act as unconstitutional under Supremacy Clause grounds.