Gerrymandering in AP US Government

Elbridge Gerry's salamander and how 40% wins three of five seats

The name comes from 1812, when Massachusetts governor Elbridge Gerry signed a district map with one district so twisted that critics said it looked like a salamander. "Gerry" plus "salamander" became gerrymander.

The trick still works the same way. Imagine a state with 5 House districts of 100 voters each. Party A has 300 voters (60%) and Party B has 200 (40%). Party B controls the state legislature, so it draws the map.

First B packs A's voters. It puts 100 A voters into District 1 and 100 more into District 2. A wins both seats easily, but every vote past a bare majority is wasted. Then B cracks the remaining 100 A voters across Districts 3, 4, and 5. Each of those districts has about 33 A voters and 67 B voters, so B wins all three. The final result is 3 seats for B and 2 for A, even though B got only 40% of the vote.

From safe seats to gridlock in Topic 2.3

The course puts gerrymandering in Unit 2, Topic 2.3 (Congressional Behavior), which asks how election processes, partisanship, and divided government shape what Congress does. Gerrymandering is one of those election processes.

The causal chain runs like this. A gerrymandered map creates safe seats where one party almost always wins. In a safe seat, the real threat to an incumbent comes from the party's own primary, not from the other party in November. So the member has a reason to vote with the party base, which pushes up partisan voting and polarization. Polarization makes compromise harder and can lead to gridlock.

Two details help on multiple choice. Gerrymandering affects the House and state legislatures, not the Senate, because senators run statewide and state lines don't change. And safe districts add to the incumbency advantage in congressional elections from Topic 5.9, since a well-drawn map protects the sitting member before the campaign even starts.

Baker v. Carr, Shaw v. Reno, and where the Court stopped

The essential knowledge says gerrymandering and unequal representation have been "partially" addressed by cases allowing equal protection challenges. Both key cases are required cases in the course.

Baker v. Carr (1962) held that federal courts can hear challenges to legislative districts under the Fourteenth Amendment's Equal Protection Clause. Before Baker, courts treated districting as a political question they wouldn't touch. Baker opened the door to the "one person, one vote" principle, the rule that districts must have roughly equal populations.

Shaw v. Reno (1993) dealt with North Carolina's oddly shaped 12th District, drawn to create a second majority-Black district. The Court ruled that a district drawn mainly on the basis of race is subject to strict scrutiny under the Equal Protection Clause. This connects to Topic 3.12 (Balancing Minority and Majority Rights), where the course lists cases that restrict majority-minority districting.

Partisan gerrymandering is a different story. In Rucho v. Common Cause (2019), the Court said claims that a map is too partisan are political questions federal courts can't decide. So the Court limits maps drawn by race and by unequal population, but it leaves partisan maps to states and voters.

Putting a gerrymander into each free-response question

In Concept Application, you might get a scenario where a state legislature redraws lines after a census and one party gains seats without gaining votes. A strong answer names the tactic (packing or cracking), then explains the effect on Congress: safe seats, primary pressure, more partisan voting.

In Quantitative Analysis, the stimulus could be a map of districts or a chart comparing a party's statewide vote share to its share of House seats. Describe the gap first, then link it to gerrymandering and to representation.

In SCOTUS Comparison, a non-required districting case is a natural pair for Baker v. Carr or Shaw v. Reno. Compare the facts, then name the clause the cases rest on, the Equal Protection Clause. In the Argument Essay, gerrymandering can serve as reasoning about representation, such as whether elected representatives in a large republic actually check faction, the argument Madison makes in Federalist No. 10.

Reapportionment, redistricting, and the gerrymander built from them

Three terms get blurred together. Reapportionment is reassigning the 435 House seats among the states after each census. Redistricting is redrawing the district lines inside a state, usually done by the state legislature, to keep populations roughly equal. Gerrymandering is redistricting done to gain an advantage.

Every gerrymander happens through redistricting, but plenty of redistricting is just routine population balancing. Both reapportionment and redistricting follow the census, so read the question closely. If it asks about reallocating House seats among the states, the answer is reapportionment. If it asks about redrawing district boundaries within a state, the answer is redistricting. If it asks about drawing lines to help a party or group, it's gerrymandering.

A second common slip is saying Shaw v. Reno banned partisan gerrymandering. Shaw was about race, and the Court has declined to strike down maps for being partisan.