What Gerrymandering Is
Gerrymandering is when political leaders redraw voting district boundaries to help their own party win more elections. After the U.S. Census is conducted every 10 years, states must redraw their voting districts based on population changes. Instead of drawing fair districts, politicians sometimes draw strange, twisted boundaries to manipulate election results. The goal is to win more seats in Congress or state legislatures without gaining more actual voter support.
How the Two Main Strategies Work
Gerrymandering uses two primary tactics. Packing means drawing district boundaries to concentrate all of the opposing party's voters into a few districts, so they win those districts by huge margins but lose in many others. Cracking means spreading the opposing party's voters thinly across many districts so they never have enough votes to win in any single district. Both strategies achieve the same result: one party wins more seats even though they may not have more total voters statewide.
Who Controls Redistricting
State legislatures have the main power to redraw voting districts every 10 years. This means the party in power in a state legislature can choose how to redraw the lines. Some states have created independent commissions to handle redistricting more fairly, but in most states, politicians still control the process. This gives elected officials the ability to pick their voters instead of letting voters pick their representatives.
Legal and Political Challenges
For many years, gerrymandering was considered a normal part of politics. However, courts have increasingly ruled that extreme partisan gerrymandering violates voters' rights. Some states have passed laws or created independent commissions to make redistricting fairer. The Supreme Court has heard several cases about gerrymandering, though it has not banned the practice outright. Racial gerrymandering, which targets voters based on race, has been ruled illegal by courts.
Real-World Effects
Gerrymandering has significant consequences for democracy. It can determine which party controls Congress or state government before any ballots are cast. It also reduces the power of voters because politicians can predetermine election outcomes. This can lead to politicians ignoring certain voters since they know they will win or lose regardless. In competitive states without gerrymandering, elections are decided by actual voter preferences rather than district boundaries. 
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