social · fairness · statistics
A fair rule, an unfair total
The same rule in every district. A different picture once the seats are added.
Each local decision follows a fair rule. When the local results are added up, the overall outcome can still be unfair. Here the rule is the same in every district: the side with more votes takes that district's one seat.
Every district uses the same fair rule. What does the national total look like?
Inside every district the votes are counted the same way and the local result matches the local votes.
Because the districts have different sizes or different margins, the national total of seats can diverge sharply from the national total of votes.
A rule that is fair at each step can still produce an overall result that looks unfair.
The mismatch comes from how the local outcomes are aggregated, not from any single local count being rigged.