District Boundaries and Malapportionment

Every district that elects one seat is supposed to represent roughly the same number of people. When it doesn't, a vote in a thinly populated district buys more influence over who wins than a vote in a crowded one, because the same single seat is being divided among fewer people. This is malapportionment, and it does not require anyone to cheat on election day. The imbalance is baked in before a single ballot is cast, simply by where the lines are drawn and how long ago.

Boundary lines control two things at once: how many voters share a seat, and which voters get grouped with which neighbors. Move a line a few blocks and you can shift a district from leaning one party to leaning another, without changing a single person's opinion, just by changing who counts as 'inside' versus 'outside' that district. Carve the same 500,000 voters into five districts of 100,000 each, or into districts ranging from 60,000 to 140,000, and you get legislatures with very different partisan outcomes from identical underlying preferences. That is why the rules for drawing and redrawing these lines matter as much as the voting rule itself.

This connects directly to gerrymandering, the deliberate shaping of boundaries for partisan advantage, and to the broader machinery of Unit 4: electoral systems only translate votes into seats fairly if the districts feeding them are themselves balanced. Malapportionment is the quieter, often unintentional cousin of gerrymandering, and both show that counting votes correctly still depends entirely on how the voting map was built in the first place.