Eminent domain refers to the power of federal and state governments to take private property for public use by paying the landowner just compensation. In other words, it is a "forced sale" of private property to the government. For example, the government might seize someone’s home for the purpose of constructing a new road through the property. The government's exercise of its eminent domain power is known as "condemnation."
In order to have a valid taking of private land, 1) The taking must be for a public purpose, and 2) just compensation must be paid. The phrase "public purpose" has been interpreted broadly. Almost anything that has something to do with benefitting the public will qualify. If the government takes private property to resell to a private developer for purpose of economic development, that qualifies as a public purpose. "Just compensation" is the fair market value of the land taken at the time of the taking.
In most cases, it is not possible to refuse an eminent domain action. The power of eminent domain is a legal right of the government. Eminent domain is allowed in the United States Constitution (Article 5) as well as state constitutions and statutes. However, it may be possible to challenge a government's eminent domain action if there is no public purpose or just compensation.
