Legal Definitions - one-person, one-vote rule

The one-person, one-vote rule is a foundational principle in American constitutional law that ensures the voting power of each individual within a state is approximately equal. This rule primarily governs how legislative districts are drawn, requiring them to contain roughly the same number of people. Its purpose is to uphold the Equal Protection Clause of the Fourteenth Amendment, preventing situations where some citizens' votes carry more weight than others simply because they live in a less populated district.

Here are some examples illustrating how the one-person, one-vote rule applies:

• State Legislative Districts: Imagine a state where, due to outdated maps, one state senate district has 200,000 residents, while an adjacent district has only 50,000 residents. Both districts elect one senator. This scenario would violate the one-person, one-vote rule. The state would be legally required to redraw its senate district boundaries so that each district contains a substantially similar number of residents, ensuring that a voter in the smaller district does not have four times the electoral influence of a voter in the larger district.

• County Commissioner Elections: Consider a large county that is divided into several districts for electing its county commissioners. Over several decades, the population has shifted significantly, with some urban districts growing to 100,000 residents while rural districts have remained at 25,000 residents. If each district still elects one commissioner, the one-person, one-vote rule would compel the county to adjust its district lines. This ensures that each commissioner represents approximately the same number of people, preventing voters in less populated rural areas from having disproportionately higher representation per person on the county commission.

• City Council Wards: A city elects its council members from five distinct wards. After a recent census, it's discovered that Ward A has 40,000 residents, while Ward E, due to new housing developments, has grown to 80,000 residents. Each ward elects one council member. This disparity would trigger the one-person, one-vote rule. The city would need to redraw its ward boundaries to equalize the populations, ensuring that a voter in Ward A does not have twice the electoral impact on the city council as a voter in Ward E.