Few Americans who criticize contemporary politics as irrational partisanship, excessively focussed on personalities over issues, or on symbolism over substantive policy, seem aware of the ubiquity of these themes in American political history. Fewer still seem willing to consider that a root cause may be the American Constitution, which sets the rules for electoral activity. In our popular culture the Constitution is holy writ bestowed on us by Olympian Founding Fathers.

But rules matter. Most other electoral democracies operate in a parliamentary system with seats apportioned through proportional representation. That system produces a wider selection of parties with broader range of political discussion and encourages parties to differentiate themselves with sharper ideological and policy focus.

Defining Democracy tells the story of New York City's experiment with proportional representation between 1937 and 1945. Presumably looking at that experiment should give us insight into how American politics might be different under different rules.

Prosterman argues that two (sometimes overlapping) constituencies campaigned for proportional representation: elite good-government types and left-wing progressives. Both hoped to use proportional representation as a lever against the political stranglehold of Tammany Hall (the local Democratic machine) over city government, although not necessarily for the same reason. The good-government folks viewed Tammany as the ultimate cesspool of municipal corruption. Left-wingers opposed Tammany because Tammany's ability to curry the favor of working-class voters through distribution of small favors undercut the potential political base for progressive politics.

They found their opening when the state legislature set up a Charter Revision Commission (CRC) in 1934 authorized to make recommendations for a new city charter. Supported by such powerful political figures as NYC mayor Fiorello La Guardia and Governor Herbert Lehman, the reform movement convinced the CRC to include a proposal for proportional representation in the referendum for the new municipal charter. Both the charter and proportional representation passed overwhelmingly (61 percent for the charter, 62 percent for PR).

In the first city election after passage of PR the results looked promising. Tammany had held sixty-two of sixty-five seats in the previous Board of Aldermen. On the new smaller city council Tammany controlled only thirteen of twenty-six seats. The other thirteen were held by a coalition of left-wing American Labor Party (ALP) members (five), Republicans (three), and good-government reformers (five City Fusion and Independent Democrats). A reform Republican independently elected as council president had authority to cast tiebreaking votes. It looked like the anti-Tammany coalition would control the council by a 14–13 vote. But when one of the ALP-ers was absent from the first council meeting, Tammany controlled the proceedings by a 13–12 vote electing their stalwarts to all standing-committee chairs. The return of the absent member (ALP-er Mike Quill) did not result in overturning that outcome. The council remained paralyzed.

Prosterman concentrates the majority of the narrative on the campaign to institute proportional representation and then the recurring efforts to overturn it finally resulting in repeal in 1947. Almost from the start Tammany Democrats and some Republicans sought repeal of PR. Election of Communist Peter Cacchione from Brooklyn in 1941, joined by fellow Communist Benjamin Davis from Harlem in 1943, gave PR opponents the potency of anticommunism to fuel their repeal efforts. They succeeded in 1947. Predictably the city council quickly reverted to overwhelming Tammany control.

While Defining Democracy presents this narrative of the initial passage of PR, efforts to defend it against critics, and final repeal clearly and in convincing detail, I would have liked to see more discussion about how New York City politics differed in the PR era from the years immediately before and after. The coalition of reformers and left-wingers never was able to sustain an effective working majority on council. Did their presence nonetheless alter the terms of debate in local political discourse both within city government and in the larger public arena? Did public policy differ in any way during these years from the years before and after? I think the answer to both questions is yes, but Defining Democracy does not explore them in detail or make that case.