At first glance, few things scream “gerrymander” like splitting the country’s largest historically black university in two. That’s what happened at North Carolina Agricultural and Technical University in 2016; a school that was once in the state’s 12th Congressional District is now in the 6th and 13th. The school is in Greensboro, where 40 percent of the population is black, and the city has also been divided in two. Both new districts are represented by white Republican men, and students have rallied against the division.

But the new lines were actually instituted as part of a remedy for a previous racial gerrymandering case. In 2016, a federal court struck down the old lines down, ruling that Republican lawmakers had packed black voters, meaning minorities were too isolated in one district to be represented fairly statewide. (To make matters more confusing, the entire state map is now being challenged in a partisan gerrymandering case.)

The back-and-forth over electoral boundaries has repeated itself for decades in Greensboro. Since 1990, the lines around the city have been redrawn six times even though there have been only three rounds of normal post-census redistricting during that period. The lines have been argued before the Supreme Court five times. In many ways, the changing lines in Greensboro illustrate a long-running debate over how to ensure minority voters are represented in government.

This is the third installment of FiveThirtyEight’s podcast series “The Gerrymandering Project,” in which we travel around the country to explore the effects of gerrymandering and what reformers are doing to change the redistricting process. In this episode, we focus on racial gerrymandering in North Carolina.

As things stand today, partisan gerrymandering is not illegal, but racial gerrymandering is. But that doesn’t mean that everyone agrees on what constitutes a racial gerrymander. The legal fight to define racial gerrymandering has raged for decades, in no small part because the answer has major implications for each party.

At the heart of that debate are majority-minority districts. A 1986 Supreme Court ruling, Thornburg v. Gingles, established that where racially polarized voting is present, it is illegal to dilute minority residents’ voting power, either intentionally or unintentionally. States across the South then drew new majority-minority districts to ensure that black voters could elect their candidates of choice. In many places, the newly drawn majority-minority districts elected those states’ first African-American congressional representatives since Reconstruction.

It was a win for African-American representation, and also a win for Republicans. By grouping together black voters, who vote overwhelmingly Democratic, the maps increased Republican electoral prospects in the surrounding districts. That dynamic has encouraged Republicans to advocate for majority-minority districts, while Democrats have been more skeptical of them.

In North Carolina, the debate over majority-minority districts often comes down to this complicated question: In a state where African-Americans vote overwhelmingly for one party, is what’s best for African-Americans the same as what’s best for Democrats?

To hear the story, click on the play button above or subscribe to The Gerrymandering Project podcast feed. And while you wait for the next episode, be sure to subscribe to our Gerrymandering Project Facebook group. It’s a place to share your experiences with and opinions about gerrymandering. We’ll be having conversations there every week.