The US has a long history of gerrymandering legislative voting districts. Is it legal?

The gerrymandering of House districts is becoming more rampant across the U.S.

The word “gerrymander” was coined in America more than 200 years ago as an unflattering way to describe the political manipulation of boundaries for legislative voting districts by those in charge of drawing them.

The word has stood the test of time, in part because American politics remain fiercely competitive. And with time and technology, politicians have become even more adept at drafting voting districts that benefit their political party.

How are voting districts drawn?

In many states, the legislature is responsible for drawing U.S. House districts, subject to the approval or veto of the governor. District maps must be redrawn every decade, after each census, to make sure that each district has about the same number of voters.

But in certain states, nothing prevents legislatures from redistricting more often.

Some states entrust redistricting to special commissions composed of citizens or bipartisan panels of politicians in an effort to limit gerrymandering.

How does a gerrymander work?

If a political party controls the legislature and governor’s office — or has such a large legislative majority that it can override vetoes — it can effectively draw districts to its advantage.

One common method of gerrymandering is for a majority party to draw voting districts that dilute the power of an opposing party’s voters by spreading them among multiple districts. Another is for the majority party to pack voters who support the opposing party into a few districts, thus allowing the majority party to win a greater number of surrounding districts.

Why is it called gerrymandering?

The term dates to 1812, when Massachusetts Gov. Elbridge Gerry signed a bill redrawing state Senate districts to benefit the Democratic-Republican Party. Some thought an oddly shaped district looked like a salamander. A newspaper illustration dubbed it “The Gerry-mander” — a term that later came to describe any district drawn for political advantage. Gerry lost reelection as governor in 1812 but won election that same year as vice president to President James Madison.

Is political gerrymandering illegal?

Not under the U.S. Constitution.

The Supreme Court, in a 2019 case originating from North Carolina, ruled that federal courts have no authority to decide whether partisan gerrymandering goes too far. Chief Justice John Roberts wrote: “The Constitution supplies no objective measure for assessing whether a districting map treats a political party fairly.”

The court noted that partisan gerrymandering claims could continue to be decided in state courts under their own constitutions and laws. Some state courts, including the North Carolina Supreme Court, have ruled they also have no authority to decide partisan gerrymandering claims.

Why are more states gerrymandering?

The urge to gerrymander can become stronger when more is at stake. For example, the 2024 elections resulted in a very slim Republican majority in the U.S. House. To try to maintain that majority in the 2026 elections, President Donald Trump urged Republican officials in Texas to redraw their congressional districts to their advantage to win additional seats. Democrats who control California’s government countered by redrawing their congressional districts to try to win more seats — a move ratified by California voters. The gerrymandering in the nation’s two most populous states led officials in other states to also redraw House districts to try to gain their parties an edge.

What does data show about gerrymandering?

Statisticians and political scientists have developed a variety of ways to try to quantify the partisan advantage that may be attributable to gerrymandering.

Republicans, who control redistricting in more states than Democrats, used the 2010 census data to create a strong gerrymander. An Associated Press analysis of that decade’s redistricting found that Republicans enjoyed a greater political advantage in more states than either party had in the past 50 years.

Democrats responded to match Republican gerrymandering after the 2020 census. An AP analysis of the 2024 elections showed a significant political tilt in one-third of the states’ congressional districts, an indicator of potential gerrymandering. But the overall number of U.S. House seats won by Republicans and Democrats aligned almost perfectly with what would have been expected based on the share of the vote that each party received in districts across the U.S.