Redistricting

Based on Wikipedia: Redistricting in the United States

The Art of Drawing Lines That Decide Elections

Every ten years, a quiet revolution reshapes American democracy. Not through votes cast or speeches given, but through lines drawn on maps. These lines determine which neighborhoods share a representative, which communities have their voices amplified, and which find themselves carved up and diluted into irrelevance.

This is redistricting—and it might be the most consequential political process most Americans never think about.

Why Maps Matter More Than You Think

Here's the basic problem: the United States House of Representatives has exactly 435 seats, a number frozen in place since 1929. But populations shift constantly. People move from the Rust Belt to the Sun Belt, from rural areas to cities, from one suburb to another. After each census—that massive once-a-decade population count required by the Constitution—states must redraw their congressional district boundaries to reflect these changes.

Some states gain seats. Others lose them. And within each state, the districts themselves must be rebalanced so that each representative speaks for roughly the same number of people.

This sounds straightforward enough. It isn't.

The Constitution gives state legislatures the power to draw these boundaries, and legislators—being human—tend to draw lines that benefit themselves and their parties. The result is gerrymandering, named after Elbridge Gerry, a Massachusetts governor who in 1812 signed a bill creating a district so contorted it resembled a salamander. A newspaper cartoon dubbed it the "Gerry-mander," and the term stuck.

The Two Great Gerrymandering Tricks

Gerrymandering works through two main techniques, and understanding them reveals how deeply maps can distort democracy.

The first is called "packing." Imagine you're trying to minimize your opponent's power. You draw one district that crams as many of their voters as possible into a single area. Sure, they'll win that district overwhelmingly—maybe eighty percent to your twenty. But you've wasted their votes. All those extra supporters beyond the fifty percent needed to win accomplished nothing.

The second technique is "cracking." This is the opposite approach: you split your opponent's voters across multiple districts, ensuring they're always just short of a majority. Forty-five percent here, forty-three percent there—close enough to feel competitive, but never quite enough to win.

Master these two techniques, and a party with forty-five percent of statewide support can sometimes capture sixty percent or more of the seats. The math of single-member districts makes this possible.

The One Person, One Vote Revolution

For most of American history, the courts stayed out of redistricting entirely. In 1946, the Supreme Court declared in Colegrove versus Green that redistricting was a "political thicket" that federal judges should avoid. Some districts had grown wildly unequal—in one extreme case, a congressional district in Texas had more than four times the population of another district in the same state—but the courts refused to intervene.

Then came the 1960s, and everything changed.

In 1962, Baker versus Carr opened the courthouse doors, ruling that federal courts could indeed review state legislative districts. A year later, Gray versus Sanders established the principle of "one person, one vote"—the idea that each citizen's vote should carry roughly equal weight. And in 1964, Wesberry versus Sanders applied this principle to congressional districts, requiring them to have populations as equal as "practicable."

These cases transformed American politics. Suddenly, the rural districts that had dominated many state legislatures for decades found their power diluted. Suburban and urban areas gained representation more proportional to their populations. The old system, where a rural voter might have three or four times the representation of a city dweller, crumbled.

The Technology Arms Race

But the one person, one vote requirement, while necessary, didn't solve gerrymandering. It just made it more sophisticated.

In the old days, drawing a gerrymander required intuition and local knowledge. You needed to know which neighborhoods leaned which way, where the partisan boundaries fell. Today, mapmakers have access to voter files, consumer data, and geographic information systems that can optimize districts down to the individual household.

Modern gerrymandering software can test thousands of possible maps in seconds, evaluating each for partisan advantage while maintaining the appearance of reasonableness. Districts still need equal populations. They still need to be contiguous—you can't have a district split into two pieces with no connection. Many states require them to be "compact," though defining compactness precisely has proved surprisingly difficult.

Within these constraints, though, the possibilities for manipulation are vast. A clever mapmaker can draw districts that look perfectly normal on a map but systematically favor one party by precisely distributing voters in the most advantageous way.

The States That Tried Something Different

Not every state leaves redistricting to its legislature. Recognizing the obvious conflict of interest—politicians drawing their own districts is a bit like students grading their own exams—some states have experimented with alternatives.

Thirteen states now use independent or bipartisan redistricting commissions: Alaska, Arizona, California, Colorado, Hawaii, Idaho, Michigan, Missouri, Montana, New Jersey, Ohio, Pennsylvania, and Washington. These commissions vary in structure. Some are truly independent, with members selected through processes designed to minimize partisan influence. Others are bipartisan, with equal representation from both major parties and sometimes tie-breaking members who must be acceptable to both sides.

Another five states—Maine, New York, Rhode Island, Vermont, and Virginia—give independent bodies the power to propose maps, but their legislatures must still approve them. This creates a kind of separation of powers: the technical work of drawing lines happens outside the legislature, but elected officials retain final say.

And then there's Arkansas, which takes a uniquely simple approach: its redistricting commission consists of just three people—the governor, the attorney general, and the secretary of state.

The States That Don't Need to Bother

Six states escape this entire process for congressional elections: Alaska, Delaware, North Dakota, South Dakota, Vermont, and Wyoming. These states have such small populations that they each receive only one representative in the House. When your entire state is a single district, there's nothing to draw.

These representatives are elected "at-large," meaning every voter in the state participates in choosing them. It's the closest thing to a statewide popular vote that exists in the House of Representatives.

Interestingly, this was once the norm. In the early republic, many states elected their representatives at-large or through multi-member districts. The shift to single-member districts happened gradually, and wasn't required by federal law until 1967, when the Uniform Congressional District Act mandated the current system.

When Courts Step In

Despite the Constitution's grant of redistricting power to state legislatures, courts have become deeply involved in the process. This happens in two main ways.

First, courts sometimes must draw maps themselves when legislatures deadlock. If a state gains or loses seats and the legislature can't agree on new boundaries in time for the next election, courts step in to ensure elections can proceed. These court-drawn maps are usually designed to be minimally partisan, though critics note that even "neutral" criteria can advantage one party over another.

Second, courts review maps challenged as unconstitutional. Racial gerrymandering—drawing lines to dilute minority voting power—has been a particular focus. The Voting Rights Act of 1965 prohibited voting practices that discriminated based on race, and its Section 5 once required certain states with histories of discrimination to get federal approval, called "pre-clearance," before changing their election laws. The Supreme Court gutted this pre-clearance requirement in 2013, but racial gerrymandering claims continue under other provisions.

Partisan gerrymandering has proved trickier. In 2019, Rucho versus Common Cause effectively closed federal courts to partisan gerrymandering claims, ruling that such questions were "political" and not suitable for judicial resolution. Even the most extreme partisan gerrymanders, the Court held, couldn't be challenged in federal court—though state courts applying state constitutions might still provide a remedy.

The Mid-Decade Controversy

Here's something that surprises many people: nothing in federal law requires states to wait for the census to redraw their maps. A state could, theoretically, redistrict before every single election.

In practice, most states don't. Many have laws specifically prohibiting mid-decade redistricting. But when Texas Republicans gained unified control of the state government in 2003, they decided to redraw the congressional map that had been put in place just two years earlier by a court. The new map transformed a seventeen to fifteen Democratic edge in the Texas congressional delegation into a twenty-one to eleven Republican advantage.

The move was legal but unprecedented in modern times, and it sparked fierce controversy. Democratic legislators fled to Oklahoma and New Mexico to deny the legislature a quorum, hoping to run out the clock on the legislative session. They failed, and the new map took effect.

The Supreme Court upheld most of the Texas redistricting in 2006, though it did strike down one district as an unconstitutional racial gerrymander. The case established that mid-decade redistricting, while controversial, is generally permissible under federal law.

The Criteria That Sound Good But Mean Little

Most states require districts to meet certain criteria beyond equal population. Districts should be "compact" and "contiguous." They should preserve "communities of interest." They should provide "fair representation."

These sound reasonable. The problem is that none of them have clear definitions.

Take compactness. A circle is obviously compact. A long, narrow tentacle stretching across a state is obviously not. But most districts fall somewhere in between, and mathematicians have developed dozens of different measures of compactness that can produce contradictory results. A district that scores well on one measure might score poorly on another.

"Communities of interest" is even vaguer. What makes a community? Shared economic concerns? Ethnic background? Media markets? Urban versus rural character? All of these have been invoked, often by people trying to justify maps that happen to benefit their party.

Even "contiguity" has its ambiguities. Must a district be connected by land, or can bodies of water count? What about districts connected only by a bridge? These seem like technicalities until you realize they can determine whether a particular gerrymander is legal.

The Case for Competition (and Against It)

Some reformers argue that districts should be drawn to maximize electoral competition—creating as many swing districts as possible where either party might win. The theory is that competitive elections force politicians to appeal to moderate voters, reducing polarization.

Others push back hard against this idea. Competitive districts, they note, mean that roughly half of voters in each district will always be disappointed with their representative. A district that votes fifty-two to forty-eight will have very different politics than one that votes seventy to thirty, but is the former really more democratic? The forty-eight percent who lost might prefer a representative from the other party to one from their own party who ignores them entirely.

There's also a tension between competitiveness and minority representation. Creating majority-minority districts—where racial minorities constitute a majority of voters—often requires drawing less competitive boundaries. The Voting Rights Act has been interpreted to require such districts in some circumstances, but they tend to "pack" minority voters in ways that reduce their influence in surrounding districts.

The Interstate Compact That Hasn't Happened

One innovative idea that's been floated involves states agreeing to draw fair maps together. The logic: if Maryland and Illinois both use independent commissions while their neighbors gerrymander aggressively, the "good" states put themselves at a disadvantage. An interstate compact could allow states to coordinate, agreeing to adopt nonpartisan redistricting only when enough other states do the same.

So far, no such compact has been approved. But the concept illustrates how deeply game theory pervades redistricting. Unilateral disarmament can feel like surrendering power with no guarantee the other side will reciprocate.

What the Future Holds

After each census, the redistricting battles begin anew. The 2020 census led to a new round of map-drawing, with some states gaining seats, others losing them, and every state with multiple districts required to adjust boundaries.

The trend toward independent commissions continues, though it's far from universal. And even "independent" commissions face criticism. Some have been accused of favoring incumbents. Others have produced maps that one party claims are biased. The dream of perfectly neutral redistricting remains elusive—perhaps because the very concept of neutrality in redistricting is contested.

Technology will keep advancing, making sophisticated gerrymandering easier and detection algorithms more powerful. Courts will continue wrestling with which kinds of boundary manipulation cross constitutional lines. And every ten years, the census will force the whole process to start over.

In the meantime, the lines on the map—invisible to most voters, incomprehensible to many, and consequential to all—will continue shaping who governs America and how.

The Deeper Question

Redistricting debates often assume that fairer maps would solve what ails American democracy. But there's a more fundamental question lurking beneath the surface: is the single-member district system itself the problem?

Most democracies use some form of proportional representation, where parties receive seats in proportion to their vote share. A party that wins forty percent of votes gets roughly forty percent of seats. Gerrymandering in such systems is either impossible or far less consequential.

The American system of single-member districts was never ordained by the Constitution—it was chosen by Congress, and Congress could change it. Some reformers advocate for multi-member districts with ranked-choice voting, which would allow voters to rank candidates by preference and ensure that representation more closely matches the electorate's preferences.

Such changes would require federal legislation and would face enormous political obstacles. They would also fundamentally alter the relationship between representatives and their constituents, replacing the idea of a single local representative with something more diffuse.

Whether that tradeoff would be worthwhile is, perhaps, the redistricting debate's deepest question—one that the current system's line-drawers have little incentive to ask.