Shoestring annexation

Municipal annexation is a process by which a municipality expands its boundaries into adjacent areas not already incorporated into the municipality. This has been a common response of cities to urbanization in neighboring areas. It may be done because the neighboring urban areas seek municipal services or because a city seeks control over its suburbs or neighboring unincorporated areas.

In the United States, all local governments are considered "creatures of the state" according to Dillon's Rule, which resulted from the work of John Forrest Dillon on the law of municipal corporations. Dillon's Rule implies, among other things, that the boundaries of any jurisdiction falling under state government can be modified by state government action. For this reason, examples of municipal annexation are distinct from annexations involving sovereign states.

In 1909 the city of Atlanta, Georgia, then located only in Fulton County, annexed part of neighboring DeKalb County, from which Fulton County had originally been divided. Because the original county borders retain legal significance, the expansion into two counties generated some problems, such as when police arrest suspects on charges set forth in Georgia state law and city police must determine to which county's jail they must be taken.

Following referenda in 1874 and 1895, the city of New York annexed portions of southern Westchester County and in 1898, after another referendum, the city annexed all of Kings, Richmond, and most of Queens counties. The annexed portion of Westchester County is now Bronx county; the unannexed portion of Queens County is now Nassau County. As a result, Westchester County does not currently include any portion of the city of New York and Queens County is entirely within the city of New York.

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