The term "takings" refers to the practice of taking, or otherwise restricting the use of, private property through the governmental power of eminent domain, environmental regulation, or other restrictions. The power of eminent domain—and the property owner's right to compensation—is stated in the Bill of Rights (Fifth Amendment to the U.S. Constitution): "nor shall private property be taken for public use, without just compensation." Likewise, the Fourteenth Amendment stipulates that no state may "deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws."

Critics of environmental regulation contend that government cannot constitutionally interfere with a property owner's freedom to do as he or she wishes with his or her own property without compensating the owner. For example, a farmer who wishes to extend or improve his land by...