Gerrymandering is the practice of drawing electoral district boundaries in a way that gives an unfair advantage to one political party, candidate, or demographic group. The goal is simple yet corrosive to democracy. By reshaping maps, those in power can turn a minority of votes into a majority of seats or neutralize opposition strongholds without changing a single law or voter preference. The term itself dates back more than two centuries, but the tactic remains a fixture of American politics and appears in varying forms around the world. Despite widespread criticism, repeated court challenges, and reform efforts, gerrymandering persists because it serves the immediate interests of the politicians who control the process. This article explains how gerrymandering works, traces its history, examines modern techniques, and explores the structural, legal, and technological reasons it continues to thrive in the twenty-first century.
The origins of the word provide a vivid illustration of the practice. In 1812 the Massachusetts state legislature, dominated by the Democratic-Republican Party, redrew congressional districts to weaken the rival Federalist Party. Governor Elbridge Gerry signed the plan into law even though one newly created district in Essex County stretched across the map in a bizarre, elongated shape. A Federalist newspaper editor noticed the resemblance to a salamander and dubbed the creature a “gerrymander,” combining the governor’s name with the mythical beast. The cartoon that accompanied the article showed the district with claws, wings, and fangs, and the label stuck. Within weeks the word entered the American political lexicon. The episode was not the first instance of map manipulation, but it gave the maneuver a memorable name that has endured.
Gerrymandering has appeared throughout United States history. Both major parties have employed it when they held the upper hand. In the decades after the Civil War, Southern Democrats used it alongside poll taxes and literacy tests to dilute the voting strength of newly enfranchised Black citizens. During the Progressive Era, urban machines in the North packed immigrant neighborhoods into single districts to limit their influence on statewide races. In the twentieth century, Republicans in the Midwest and Democrats in the South refined the art to protect incumbents and maximize partisan gains. The practice survived the civil-rights reforms of the 1960s because the Supreme Court initially treated it as a political question beyond federal judicial review. Only later did courts begin to scrutinize maps when they appeared to violate constitutional protections or federal statutes.
At its core, gerrymandering relies on two complementary strategies known as packing and cracking. Packing concentrates as many voters from the opposing party as possible into a handful of districts. Those districts become overwhelmingly safe for the opposition, but the surplus votes are wasted because they exceed what is needed to win. Cracking spreads the remaining opposition voters thinly across many other districts so that they form minorities everywhere and cannot secure a plurality in any of them. A party that controls the redistricting process can therefore win a comfortable majority of seats even if it receives a minority or a bare plurality of the statewide popular vote. Sophisticated practitioners combine both techniques, sometimes creating a few extremely safe districts for themselves while ensuring that competitive areas lean slightly in their favor. The result is a map that looks normal on paper yet produces skewed outcomes.
Modern gerrymanders have become far more precise than their nineteenth-century predecessors. Lawmakers once relied on paper maps, census data, and rough estimates of voter behavior. Today they use powerful geographic information systems, detailed precinct-level voting records, demographic projections, and advanced statistical models. Software packages allow mapmakers to test thousands of possible district configurations in minutes and select the one that maximizes seats while satisfying minimal legal requirements such as equal population and contiguity. Political consultants feed these programs with granular data on past turnout, party registration, and even consumer habits that correlate with voting preferences. The result is surgical precision. A well-crafted gerrymander can withstand small shifts in voter sentiment and remain effective for an entire decade until the next census.
Partisan gerrymandering is not the only variety. Racial gerrymandering occurs when districts are drawn predominantly on the basis of race to either concentrate or fragment minority voters. After the passage of the Voting Rights Act in 1965, some states created majority-minority districts to comply with federal requirements and ensure minority representation. Other states, however, drew lines to dilute minority voting power by cracking Black or Hispanic communities across multiple districts. The Supreme Court has ruled that race cannot be the predominant factor in drawing districts unless the map satisfies strict scrutiny under the Fourteenth Amendment. In practice, distinguishing between permissible compliance with the Voting Rights Act and impermissible racial manipulation remains difficult and frequently leads to litigation.
The United States Supreme Court has shaped the legal landscape surrounding gerrymandering in important ways. In a series of cases beginning in the 1960s the Court established the one-person, one-vote principle, requiring districts to have roughly equal populations. It later struck down some racial gerrymanders but left partisan gerrymandering largely untouched. The landmark 2019 decision in Rucho v. Common Cause held that federal courts could not review claims of excessive partisan gerrymandering because such disputes presented political questions best left to legislatures and state courts. Chief Justice John Roberts wrote that the Constitution does not provide a clear standard for measuring when partisan mapmaking crosses into unconstitutionality. The ruling effectively closed the federal courthouse door for most partisan claims while leaving racial claims and state-law challenges intact. Several states responded by strengthening their own standards or creating independent commissions, but the decision removed a powerful national check.
State courts have sometimes filled the gap. In Pennsylvania, North Carolina, and Wisconsin, judges have invalidated maps found to violate state constitutional guarantees of free and equal elections. Yet these victories are episodic. When one court strikes down a map, the legislature often draws another that achieves similar results through subtler means. The cycle of litigation consumes years and resources while the challenged maps remain in effect for one or more election cycles. Meanwhile, the decennial redistricting process after each census offers fresh opportunities for mapmakers to reset the board.
Why does gerrymandering endure despite near-universal condemnation from good-government groups, editorial boards, and large segments of the public? The most straightforward answer is self-interest. In forty-four states the state legislature plays a direct role in drawing congressional and state legislative districts. The party that controls the legislature and the governorship, or at least can override a veto, has every incentive to design maps that entrench its own power. Incumbent lawmakers of both parties benefit from safe districts that reduce the risk of primary challenges from more extreme candidates or general-election defeats. Even when public opinion shifts, gerrymandered maps can delay the translation of that shift into legislative majorities for several election cycles.
Technological advancement has lowered the barriers to effective gerrymandering and raised the rewards. In earlier decades a clumsy map might backfire if demographic changes or turnout surprises undermined the intended advantage. Contemporary tools minimize that risk. Mapmakers can now simulate hundreds of election scenarios under different turnout models and select configurations that perform well across a wide range of plausible futures. The same data-driven approach that helps campaigns target individual voters also helps line-drawers predict exactly where to place district boundaries for maximum partisan yield. This precision makes gerrymandering less detectable to the naked eye. Districts no longer need to resemble salamanders; they can appear compact and logical while still producing lopsided outcomes.
Institutional design reinforces the problem. Most states lack independent redistricting commissions with binding authority. Where commissions exist, their rules and membership often reflect compromises that leave room for partisan influence. Citizen-initiated ballot measures in states such as California, Michigan, and Colorado have created more neutral processes, yet these reforms cover only a fraction of the country. In the remaining states, politicians retain control and have little reason to surrender it voluntarily. Federal legislation that would have imposed national standards or required independent commissions has repeatedly failed in Congress because the beneficiaries of the current system hold the votes needed to block change.
Public apathy also plays a role. Many voters pay little attention to the redistricting process, which occurs behind closed doors in state capitols every ten years and involves technical details that seem distant from daily life. Low turnout in primary elections further entrenches incumbents in safe districts. When districts are drawn to be overwhelmingly Democratic or Republican, the general election becomes a formality and the real contest shifts to the primary, where the most ideologically committed voters dominate. This dynamic contributes to greater polarization in Congress and state legislatures. Representatives have fewer incentives to compromise or appeal to the political center when their reelection depends on satisfying the base rather than winning swing voters.
The consequences extend beyond partisan seat counts. Gerrymandering undermines the principle that voters should choose their representatives rather than the reverse. It depresses turnout because residents in safe districts feel their votes matter less. It can produce state delegations or congressional majorities that do not reflect statewide or national popular sentiment. In several recent election cycles, one party has secured a majority of House seats while the other received more total votes nationwide. Such discrepancies erode trust in the fairness of elections and fuel cynicism about democratic institutions. When combined with other factors such as campaign-finance rules and media fragmentation, gerrymandering helps sustain a political environment in which compromise is rare and gridlock is common.
Racial dimensions add another layer of concern. Even after the Voting Rights Act, some maps have been challenged for diluting minority voting strength. The Supreme Court weakened key provisions of the Act in Shelby County v. Holder in 2013 by striking down the coverage formula that required certain jurisdictions to obtain federal preclearance before changing voting rules. The decision led to a new wave of voting laws and redistricting plans that advocates argued suppressed minority participation. Subsequent litigation has produced mixed results, but the overall effect has been to make racial gerrymandering harder to police in some regions.
Reform efforts continue at the state level. Independent commissions have produced more competitive maps in the states that adopted them. Some states have enacted rules requiring districts to be reasonably compact, to respect county or municipal boundaries, or to preserve communities of interest. Scholars have developed quantitative metrics such as the efficiency gap, which measures the difference between each party’s wasted votes, and partisan symmetry tests that assess whether a map treats both parties equally under hypothetical uniform swings in vote share. These tools help courts and commissions identify outliers, though they do not eliminate all disagreement over what constitutes fairness.
Advocacy organizations, academic researchers, and some political insiders have proposed more radical solutions. One idea is to replace single-member districts with multi-member districts elected by proportional representation or ranked-choice voting. Such systems would make gerrymandering far more difficult because seat allocation would track vote shares more closely. Another proposal involves computer algorithms that generate thousands of random maps meeting neutral criteria and then select the one that best satisfies additional fairness standards. Pilot programs in a few localities have tested these approaches, but scaling them nationally would require broad political consensus that currently does not exist.
Gerrymandering also appears in other democracies that use single-member districts, such as the United Kingdom and Canada, though usually to a lesser degree because of stronger independent boundary commissions. In countries with proportional representation systems the problem is minimized because seat allocation follows vote totals more directly. The persistence of gerrymandering in the United States therefore reflects a combination of institutional choices, partisan incentives, and technological capability rather than any inevitability of human nature.
In the end, the survival of gerrymandering reveals a fundamental tension in representative democracy. The people who draw the lines are the same people who benefit most from the lines they draw. Until voters demand change through ballot initiatives, state constitutional amendments, or sustained pressure on legislatures, or until courts and commissions impose stricter nationwide standards, the practice will continue. Public awareness has grown, and data transparency has improved, yet the fundamental incentives remain unchanged. Gerrymandering endures not because it is invisible or inevitable, but because the political system that permits it has yet to muster the collective will to restrain it. The maps of the next decade will be drawn soon after the 2030 census. Whether they reflect genuine competition or calculated advantage will depend on the vigilance of citizens, the creativity of reformers, and the willingness of courts to enforce whatever limits the law and state constitutions allow. The history of the salamander suggests that the temptation to manipulate boundaries is as old as democratic elections themselves. The question for the present generation is whether that temptation can finally be brought under meaningful control.