"One person, one vote" doctrine practical implication for legislative districting?

• A. Districts must have the same geographic area.
• B. Legislative districts must have substantially equal populations to ensure equal representation.
• C. Voting rights require federal preclearance; Shelby County v. Holder and Smith v. Allwright.
• D. Equal protection prohibits any population disparities; Shaw v. Reno and Brown v. Board.

Answer: (B)

The practical implication is that legislative districts must be drawn so each vote carries roughly equal weight by ensuring substantially equal populations across districts. This requirement, established under the one person, one vote principle, means states redraw district lines after each census to keep districts about the same size in population, not the same geographic area. Geographic area can vary, but population parity is key to fair representation.

So why this is the best fit: equal representation comes from making each district contain about the same number of people, preventing vote dilution. Redistricting after every census is the mechanism to maintain that balance. While other factors like contiguity and community interests matter, they do not override the core need for population equality.

The other ideas aren’t the focus here: requiring districts to cover equal geographic areas isn’t necessary, federal preclearance concerns Voting Rights Act enforcement, and while equal protection limits racial gerrymandering, it does not ban all disparities—substantial equality, not perfect parity, is the standard.