Federal preemption refers to the invalidation of a US state law when it conflicts with Federal law.

According to the Supremacy Clause (Article VI, clause 2) of the United States Constitution,

This Constitution, and the Laws of the United States which shall be made in Pursuance thereof ... shall be the supreme Law of the Land; ... any Thing in the Constitution or Laws of any state to the Contrary notwithstanding.

As the Supreme Court stated in Altria Group v. Good, 555 U.S. 70 (2008), a federal law that conflicts with a state law will trump, or "preempt", that state law:

Consistent with that command, we have long recognized that state laws that conflict with federal law are “without effect.” Maryland v. Louisiana, 451 U. S. 725, 746 (1981)

In Altria Group v. Good, the Court wrote:

When the text of a pre-emption clause is susceptible of more than one plausible reading, courts ordinarily “accept the reading that disfavors pre-emption.” Bates v. Dow Agrosciences LLC, 544 U. S. 431, 449 (2005).

In Wyeth v. Levine (2009), the Court emphasized what it called the "two cornerstones" of pre-emption jurisprudence:

Jere Locke Beasley (born December 12, 1935) was the acting governor of the US state of Alabama from June 5 to July 7, 1972.

Born in Tyler, Texas, to Browder Locke and Florence Camp Beas. He was raised in Clayton, Alabama. In 1958, he married Sara Baker.

Beasley received his B.S. degree from Auburn University and his J.D. from the University of Alabama School of Law. He worked for various law firms until he opened his own practice in 1965.

He was the 22nd Lieutenant Governor when Governor George Corley Wallace was shot and severely injured in an assassination attempt in Laurel, Maryland, on May 15, 1972. Since Wallace was out-of-state for more than 20 days, recovering in a Maryland hospital, the Alabama Constitution required that the lieutenant governor take over in the interim.

Beasley won the first round of Democratic primary for lieutenant governor in 1970, but failed to win a majority. He won the runoff. In 1974 he faced a strong challenge from Charles Woods, who finished first in first round. Beasley, however, again won the runoff. He sought nomination for governor in 1978, but finished a distant fifth.

Jeb Hensarling (born May 29, 1957) has been the Republican congressman representing Texas' 5th congressional district (map) in the United States House of Representatives since 2003.

Hensarling was born in Stephenville, the seat of Erath County, and grew up on the family farm in College Station. He graduated from Texas A&M University in 1979 with a bachelor's degree in economics. In 1982, he earned a Juris Doctor degree from the University of Texas at Austin. He is also an Eagle Scout.

Prior to serving in Congress, Hensarling was State Director for Texas Senator Phil Gramm from 1985 until 1989. From 1991 to 1993, he served as executive director of the Republican Senatorial Committee.

Hensarling next served as a vice president at two different companies before becoming owner of San Jacinto Ventures in 1996 and CEO of Family Support Assurance Corporation in 2001. He served as vice president of Green Mountain Energy from 1999 to 2001.

Hensarling was elected to his first term in 2002, defeating Democratic opponent Ron Chapman with 58 percent of the vote. He was reelected in 2004 with 64 percent of the vote over Democratic challenger Bill Bernstein.

Jan Richard Schlichtmann (born March 16 1951) is an American attorney specializing in personal injury law and toxic torts. He was educated at the University of Massachusetts Amherst, B.A., and Cornell University, J.D., and was admitted to the bar in 1977.

German American attorney Schlichtmann became famous in the 1980s as a result of his lawsuit against W. R. Grace and Beatrice Co. (Anderson v. Cryovac) alleging that chemicals from these companies had contaminated drinking water in a town north of Boston, Woburn, Massachusetts. Extensive tests by Schlichtmann's experts and the Harvard School of Public Health showed that defendants W. R. Grace and Beatrice Co. had polluted Woburn's water with dangerous levels of various carcinogenic chemicals.

The contamination is alleged to have resulted in the deaths of children from leukemia. This civil action case, often referred to as "Woburn," was chronicled in the 1995 book A Civil Action by Jonathan Harr, which in turn was made into a film starring John Travolta as Schlichtmann.

Catherine Moira Sharkey (born c. 1970) is a professor of law at the New York University School of Law. Her scholarship focuses torts, punitive damages, class actions, remedies, products liability, and empirical legal studies.

Sharkey graduated from Yale University, (Skull and Bones 1992), and went on to the University of Oxford as a Rhodes scholar. She then attended Yale Law School, where she was Executive Editor of the Yale Law Journal. She clerked for Judge Guido Calabresi of the United States Court of Appeals for the Second Circuit, and for Justice David H. Souter of the United States Supreme Court.

Before joining the faculty at Columbia Law School and later NYU School of Law, Sharkey worked for several years as an appellate litigation associate at Mayer Brown in New York.

Sharkey is occasionally mentioned as a potential future United States Supreme Court nominee.