In trying to take land for the wall, the federal government would be held to time-consuming procedures that include consultation and negotiation with the affected parties — including private landowners, tribes, and state and local governments — before taking any action. Federal law requires the government to consult with “property owners … to minimize the impact on the environment, culture, commerce, and quality of life for the communities and residents located near the sites at which such fencing is to be constructed.” Then the government would need to declare a taking and undergo condemnation proceedings….

The takings clause [of the Fifth Amendment] also protects private landowners from uncompensated seizures. Owners who are subject to eminent domain to build the wall would have to receive compensation for its physical presence on their property. Successfully measuring the value of the land and settling on prices for hundreds of owners with unique property interests, however, would be the “deal” of the century. Determining just compensation is not easy in contested cases in which the land and property at stake are infrequently exchanged on the market. There are few other properties in the United States situated along an international boundary, some of which is already fenced, which makes fair value hard to establish….

[T[hat’s a lot of ammunition for hundreds of landowners. If the rollout of Trump’s hastily drafted travel ban is any indicator, we should expect sloppy execution of statutory requirements and takings procedures if the administration attempts to condemn border land.