Ehrenpromotion Professor em. Michel Balinski, Ph.D.
CNRS und École Polytechnique, Paris

»Computing Electoral Districts«




On April 28, 2004 the United States Supreme Court announced its decision in the case of Vieth v. Jubelirer. It refused to declare unconstitutional Pennsylvania's new map of 19 congressional districts (based on the census of 2000, first used in the 2002 elections). Its bizarrely shaped districts have been compared to animals: the "supine seahorse" and the "upside-down Chinese dragon." By all accounts Pennsylvania slightly favors the Democratic Party. In the elections of 2000 (when the state had 21 seats) it elected 11 Republicans and 10 Democrats (while giving Gore 50.6% and Bush 46.4% in the state-wide vote); in 2002, with the new map, it elected 12 Republicans and 7 Democrats (while giving a Democratic gubernatorial candidate 55% in the state-wide vote). Five Republican candidates ran unopposed, one Democratic candidate ran unopposed. The map "kidnapped" three Democratic incumbents; it systematically "cracked" Democratic voters among districts; and "packed" and "stacked" them into districts. Yet the map is "perfect": every district has either 646,371 or 646,372 inhabitants. Not one Justice denied that the map is a blatant political gerrymander ("the practice of dividing a geographical area into electoral districts, often of highly irregular shape, to give one political party an unfair advantage by diluting the opposition's voting strength").


Texas, with its new congressional map, elected 17 Democratic and 15 Republican Representatives in 2002, and also gave absolute political control of the State government to the Republicans. The new State government immediately redrew the map of the congressional districts. It is widely agreed that in the 2004 elections Texas will elect 10 Democrats (perhaps 9) and 22 (perhaps 23) Republicans. Yet every district has either 651,619 or 651,620 inhabitants. Gerrymandering is perfectly ecumenical: the Democrats believe in it as much as their Republican brethren. In Maryland the map drawn by the Democrats changed what had been an equal division of the seats into a 6 to 2 split to their advantage and deliberately eliminated a targeted incumbent. In Georgia the Democrat's map increased their congressional delegation by two and successfully "kidnapped" a manager of the effort to impeach President Clinton (despite the loss of one Senator and the governorship in state-wide races). California's map is bipartisan ? yet suspect: 50 of 53 Representatives including every incumbent candidate was elected with at least 60% of the votes in 2002.


These instances, and others, have provoked a public outcry: district maps determine the winners, not elections!


Why and how has this happened? First, Supreme Court decisions have set precedents that are confused and often contradictory. Second, new computer technology has permitted maps and their political implications to be defined easily and quickly. Third, the increasingly predictable behavior of voters has made the political implications of district lines more accurate.


In the opinion of the plurality (four of nine) in the case of Vieth v. Jubelirer, claims of partisan gerrymandering should be "nonjusticiable because no judicially discernible and manageable standards for adjudicating such claims exist." Their reason (if not their reasoning) is sound: there is no theory or body of knowledge capable of distinguishing which of two district maps is "fairer". If single-member constituencies are to remain in use (and they exist in many countries) then a central problem in the mathematics of political systems is to develop rigorous criteria for "fair districting" ? or to show that it is impossible to do so.


The U.S. Supreme Court's ruling and opinion will no doubt open the floodgates, provoking new gerrymanders wherever one of the two parties has absolute political control of the State. A swing of as much as 5% of the vote from the Republicans to the Democrats is already expected to result in practically no increase of Democratic representation. A major crisis threatens the democratic institutions of the nation.


The judicial system has proved itself incapable of providing relief. Congress has the constitutional right to impose a fair electoral system. What should the Congress do? The problem is at once urgent and important.


This talk will outline the problem in the context of the current situation in the United States, and will advance several tentative answers.