Proportional Representation in American Cities

Ranked-choice voting is a popular idea, and its multi-winner form makes winning office easy. Americans once called this proportional representation via the single transferable vote (STV) — "PR" for short. How might this be adopted? Under what conditions is it stable? Why not some other form of PR? We can begin to answer these questions by looking at the 24 cases in American history, 1915-62.

[Click to see data from a U.S. multi-party legislature.]

[Click to read the dissertation as defended.]

[Click to watch a webinar where I discuss my findings.]

Sitting politicians did not enact STV. Rather, two or more groups would agree to work around them: a faction of the ruling party and one or more minority parties. Ruling-party factions did this when nominating systems shut them out. Minority parties did it in order to win more seats.

Demand for "unbossed" elections explains the ranked-choice form that PR took. Dominated factions wanted as little party control of ballot access as possible, as well as control of how votes might flow among parties. Only STV could satisfy this consitituency, plus the people seeking party-level proportionality.

Repeal campaigns took shape when the second-largest party stopped getting what it wanted. Parties in government could move between coalitions, and so could individual legislators. If a party's leaders encountered either problem, they asked whether their party was large enough to survive under plurality voting. If it was, those leaders made deals with opposing parties to repeal STV.

Why is "multi-winner ranked-choice voting" popular again? Elections below the presidential level are less competitive than they have been in decades. This produces parties willing to consider proportionality. At the same time, people in both parties feel shut out, a reason to consider anti-party reforms.

Data & approach

Others have studied the PR cities. This project's contribution is to systematically compare: PR adoptions to non-adoptions, parties of high and low cohesion, and legislative sessions that did and did not precede repeal efforts.

I draw on newspapers, archival material, and newly digitized data from five large cities. My methods include structured focused comparison, classical regression, ecological inference, and ideal point estimation. An in-progress chapter uses automated text analysis.

The first part of the book project reconstructs charter change events with different outcomes in three most-similar cities. Then I see if the patterns are consistent with aggregate data on the wider universe of 20th-century city charter reforms.

Remaining chapters consider politics within the PR cities. First I account for varied legislative cohesion. Then I explain the timing of PR repeal attempts. These chapters use 52 city-years of roll-call voting in three most-different and plausibly representative cases: Cincinnati (1929-57); New York City (1938-47); and Worcester, Mass., (1950-60). These data amount to 5,127 hand-coded roll-call votes, 126 unique legislators, 1,011 rounds of vote-counting under the single transferable vote, 1,001 candidates, and their party affiliations over 25 elections (20 of which had party-free ballots).

Here is a taste of the roll-call data. This is a spatial representation of voting in the PR-elected New York City Council. Included are eventual Congressman Adam Clayton Powell, Jr. and 1928 Democratic presidential candidate Al Smith. I used Keith Poole's optimal classification algorithm to generate constant ideal points. Model fit is very good. The horizontal axis is support for Tammany Hall. The vertical axis can be thought of as support for Robert Moses.

New York City repealed PR in 1947 when Republican and Democratic leaders joined forces. Three things provoked that alliance. First, the GOP had lost control of the mayoralty and Board of Estimate because the ALP switched in 1945 to endorsing Democrats. Second, as shown below, the GOP stops voting as a bloc. Third, the GOP rebounds electorally, suggesting it might survive the return to plurality voting. Why did Tammany go along with repeal? We also see some Democrats breaking ranks with their party. That group will appear toward the bottom of the image.