¹ For the distinction between political and bureaucratic corruption, see Rose-Ackerman, Susan, Cor-ruption:A Study in PoliticalEconomy (New York: Academic Press, 1978)Google Scholar.

² Although political corruption encompasses a broader set of activities, the receipt of funds in exchange for favors is especially important, both because of the potentially distortionary economic effects of these activities and because they are almost always illegal. When elected officials persistently engage in illegal behavior, troubling consequences arise for the democratic order.

³ Torsten Persson, Guido Tabellini, and Francesco Trebbi, “Electoral Rules and Corruption” (Manuscript, Institute for International Economic Studies, Stockholm University, November 2000).

⁴ For instance, Mitchell, Paul, “Voters and Their Representatives: Electoral Institutions and Delegation in Parliamentary Democracies,” European Journal of Political Research 37 (May 2000)CrossRefGoogle Scholar.

⁵ Those whose work supports this view include Ames, Barry, “Electoral Strategy under Open-List Proportional Representation,” American Journal of Political Science 39 (May 1995)CrossRefGoogle Scholar; Cain, Bruce, Ferejohn, John, and Fiorina, Morris, The Personal Vote: Constituency Service andElectoralIndependence (Cambridge: Harvard University Press, 1987)CrossRefGoogle Scholar; Carey, John M. and Shugart, Matthew Soberg, “Incentives to Cultivate a Personal Vote: A Rank Ordering of Electoral Formulas,” Electoral Studies 14 (December 1995)CrossRefGoogle Scholar; Fiorina, Morris P. and Noll, Roger, “Voters, Bureaucrats and Legislators: A Rational Choice Perspective on the Growth of Bureaucracy,” Journal of Public Economics 9 (April 1978)Google Scholar; idem, “Voters, Legislators and Bureaucracy: Institutional Design in the Public Sector,” American Economic Review Papers and Proceedings 68 (May 1978)Google Scholar; Barbara Geddes and Artur Ribeiro Neto, “Institutional Sources of Corruption in Brazil,” Third World Quarterly 13, no. 4 (1992); and Samuels, David J., “Incentives to Cultivate a Party Vote in Candidate-Centric Electoral Systems: Evidence from Brazil,” Comparative Political Studies 32 (June 1999)CrossRefGoogle Scholar.

⁶ Cain, Ferejohn, and Fiorina (fn. 5).

⁷ See Miriam A. Golden, “The Effects of the Personal Vote on Political Patronage, Bureaucracy and Legislation in Postwar Italy” (Manuscript, University of California at Los Angeles, May 2001).

⁸ See Carey and Shugart (fn. 5).

⁹ Note as well that electoral systems are so rarely modified that studying the effects of change across time within countries generates only a handful of cases.

¹⁰ Seefn. 3.

¹¹ The TI index fails to distinguish political from bureaucratic corruption, and the latter is undoubtedly more common than the former. We have no reason to believe that Italy's location in the index would change, however, even if the index were confined to political corruption for the period through the mid-1990s; if anything, the Italian case would probably become relatively even more extreme. After the mid-1990s the TI index for Italy is probably capturing bureaucratic corruption, earlier political corruption, or some combination. See below (fn. 87) for further discussion.

¹² Treisman, Daniel, “The Causes of Corruption: A Cross-National Study,” Journal of Public Economics 76 (June 2000)CrossRefGoogle Scholar; see also Ades, Alberto and Di Tello, Rafael, “Rents, Competition, and Corruption,” American Economic Review 89 (September 1999)CrossRefGoogle Scholar.

¹³ Cazzola, Franco and Morisi, Massimo, “Magistratura e classe politica: due punti di osservazione specifici per una ricerca empirica,” Sociologia del Diritto 22, no. 1 (1995), 101–2Google Scholar.

¹⁴ Most importantly, Cazzola, Franco, Delia corruzione: fisiologia e patologia di un sistema politico (Bologna: II Mulino, 1988)Google Scholar; and Porta, Donatella della, Lo scambio occulto: casi di corruzionepolitica in Italia (Bologna: II Mulino, 1992)Google Scholar.

¹⁵ Among others, Cazzola, Franco, L'ltalia delpizzo:fenomenologia della tangente quotidiana (Turin: Einaudi, 1992)Google Scholar; Alessandro Pizzorno, “Introduzione: la corruzione nel sistema politico,” in della Porta (fn. 14); Franco Cazzola, “Storia e anatomia della corruzione in Italia,” IIPolitico 13 (April 1993); Ricolfi, Luca, L'ultimo Parlamento: sullafine dellaprima Repubblica (Rome: La Nuova Italia Scientifica, 1993)Google Scholar; Porta, Donatella della and Vannucci, Alberto, Corruzionepolitica e amministrazionepubblica: risorse, meccanismi, attori (Bologna: II Mulino, 1994)Google Scholar; Mauro Magatti, Corruzione politica e societa italiana (Bologna: II Mulino, 1996); and Vannucci, Alberto, Il mercato della corruzione: i meccanismi dello scam-bio occulto in Italia (Milan: Societa Aperta, 1997)Google Scholar.

¹⁶ Including Porta, Donatella della and Vannucci, Alberto, “Politics, the Mafia, and the Market for Corrupt Exchange,” in Mershon, Carol and Pasquino, Gianfranco, eds., Italian Politics: Ending the First Republic, vol. 9 of Italian Politics: A Review (Boulder, Colo.: Westview Press, 1995)Google Scholar; Waters, Sarah, “‘Tangentopoli’ and the Emergence of a New Political Order in Italy,” West European Politics 17 (January 1994)CrossRefGoogle Scholar; Moss, David, “Patronage Revisited: The Dynamics of Information and Reputation,” Journal of Modern Italian Studies 1 (Fall 1995)CrossRefGoogle Scholar; Porta, Donatella della and Pizzorno, Alessandro, “The Business Politicians: Reflections from a Study of Political Corruption,” Journal of ‘Lam and Society’ 23 (March 1996)Google Scholar; Hine, David, “Political Corruption in Italy,” in Little, Walter and Posada-Carbo, Eduardo, eds., Political Corruption in Europe andLatin America (Bassingstoke: Macmillan, 1996)Google Scholar; Rhodes, Martin, “Financing Political Parties in Italy: A Case of Systemic Corruption,” West European Politics 20 (January 1997)CrossRefGoogle Scholar; Burnett, Stanton H. and Mantovani, Luca, The Italian Guillotine: Operation Clean Hands and the Overthrow ofItaly's First Republic (Lanham, Md.: Rowman and Littlefield, 1998)Google Scholar; and Porta, Donatella della and Vannucci, Alberto, Corrupt Exchanges: Actors, Resources, and Mechanisms of Political Corruption (New York: Aldine de Gruyter, 1999)Google Scholar.

¹⁷ Colombo, Gherardo, Il vizio della memoria (Milan: Feltrinelli, 1996)Google Scholar; Davigo, Piercamillo, La giubba del re. Intervista sulla corruzione, ed. Pinardi, Davide (Rome: Laterza, 1998)Google Scholar; and Antonio Di Pietro, Intervista su Tangentopoli, interview with Giovanni Valentim (Rome: Laterza, 2000).

¹⁸ Especially Ades and DiTello (fn. 12); Persson, Tabellini, and Trebbi (fn. 3); and Treisman (fn. 12).

¹⁹ Katz, Richard S., “Intraparty Preference Voting,” in Grofman, Bernard and Lijphart, Arend, eds., Electoral Laws and Their Political Consequences (New York: Agathon Press, 1986)Google Scholar.

²⁰ Samuels (fn. 5).

²¹ Linda Bull, “Public Money, Political Parties, and Corruption: The Italian Case,” Italian Politics and Society: The Review of the Conference Group on Italian Politics and Society 48 (Autumn 1997). Th putative impact of this law is analyzed below.

²² Cox, Gary W. and Thies, Michael F., “The Cost of Intraparty Competition: The Single, Non Transferable Vote and Money Politics in Japan,” Comparative Political Studies 31 (June 1998)CrossRefGoogle Scholar.

²³ Documented in Eric C. C. Chang, “The Institutional Roots of Political Corruption in Postwar Japan” (Manuscript, Department of Political Science, University of California at Los Angeles, January 2000); and Cox, Gary W. and Thies, Michael F., “How Much Does Money Matter: ‘Buying’ Votes in Japan, 1967–1990,” Comparative Political Studies 33 (February 2000)CrossRefGoogle Scholar.

²⁴ Delia Porta and Vannucci (fn. 15), 225–26.

²⁵ Wertman, Donald, “The Italian Electoral Process: The Elections of June 1976,” in Penniman, Howard R., ed., Italy at the Polls: The Parliamentary Elections of 1976 (Washington, D.C.: American Enterprise Institute for Public Policy Research, 1977), 76Google Scholar. While Wertman nowhere specifically mentions illegality as a means of raising campaign funds, he repeatedly stresses that “little, in fact, is known about the sources of factional funds” (p. 77).

²⁶ Delia Porta and Vannucci (fn. 15), 236.

²⁷ For a description of the law in English, see Wertman (fn. 25), 77.

²⁸ Useful discussions include Lancaster, Thomas D. and Montinola, Gabriella R., “Toward a Methodology for the Comparative Study of Political Corruption,” Crime, Law and Social Change 27, nos. 3–4 (1997)CrossRefGoogle Scholar; and Lambsdorff, Johann G., “Corruption in Comparative Perspective,” in Jain, Arvind K., ed., Economics of Corruption (Boston: Kluwer, 1998)Google Scholar.

²⁹ For instance, Cazzola (fn. 14), chap. 3.

³⁰ See della Porta (fn. 14); della Porta and Vannucci (fn. 15); della Porta and Vannucci (fn. 16); and Vannucci (fn. 15).

³¹ As of November 1993 the judiciary was automatically allowed to proceed unless an absolute majority voted against the request. This change in procedure greatly facilitated the Clean Hands investigations in the 1990s.

³² Cazzola (fn. 14), 113, table IV. 1.

³³ Cazzola (fn. 14); Cazzola (fn. 15); Cazzola and Morisi (fn. 13); Cazzola, Franco and Morisi, Massimo, La mutua diffidenza: ilreciproco controllo tra magistral e folitki nellaprima Repubblica (Milan: Feltrinelli, 1996)Google Scholar; and Ricolfi (fn. 15).

³⁴ We tested this hypothesis only for Christian Democratic legislators because our full data set did not separate out “opinion” crimes from other types of charges for members of other parties; for a discussion of types of charges, see pp. 600—601.

³⁵ Cazzola (fn. 14) distinguishes corruption from other types of suspected malfeasance, but he does not detail his coding procedures, making evaluation of them impossible. Hence, we chose not to use his classification. His study classed 40 percent of the RAP against DC parliamentarians between 1948 and 1987 as involving political corruption.

³⁶ Ricolfi(fn. 15), 151–64.

³⁷ This procedure was suggested to us by Davide Petrini. The exact statutes dropped from the analysis were numbers 341–42 and numbers 594–99.

³⁸ Gambetta, Diego, The Sicilian Mafia: The Business ofPrivate Protection (Cambridge: Harvard University Press, 1993), 6–7Google Scholar.

³⁹ The charge that by failing to denounce corruption in the ruling parties the PCI thereby colluded in it has been made by Silvia Colazingari and Susan Rose-Ackerman, “Corruption in a Paternalistic Democracy: Lessons from Italy for Latin America,” Political Science Quarterly 113 (November 1998). It also underlies Alessandro Pizzorno's characterization of Italy's postwar political system as a “consoci-ational” arrangement between government and opposition elites; see Pizzorno, , “Le difficolta del conso-ciativismo,” in idem, Le radici dellapolitka assoluta e altri saggi (Milan: Feltrinelli, 1993)Google Scholar; and idem (fn 15). This view fails to acknowledge the difficulties that must have been experienced by the PCI and such little independent press as existed in Italy in obtaining credible information about political corruption, given a system in which those involved in it systematically covered up for each other.

⁴⁰ The same is not true of accusations of libel, slander, and defamation of character, which apparently often came from political rivals within the same party. By omitting cases involving such charges, we remove this potential source of bias.

⁴¹ Since the present analysis is confined to the DC and omits charges of insult of a public official (statute no. 341) and insult of the state (statute no. 342), this does not pose a problem for us.

⁴² Delia Porta and Vannucci (fn. 16,1999), 141–44.

⁴³ Burnett and Mantovani (fn. 16).

⁴⁴ For instance, the magistrates involved in the Milan pool were themselves affiliated with a variety of political parties or with no party at all; some had left-wing political histories but some did not, and so on. Even Burnett and Mantovani (fn. 16), although arguing this position, do not offer persuasive and thorough documentation supporting the contention that the Milanese judiciary was politically compact.

⁴⁵ Ultimately, only additional research into the postwar Italian judiciary will allow us to distinguish more fully our measure of suspected political wrongdoing from judicial independence. One possible measure of potential judiciary autonomy is the extent of resources available to different judicial offices throughout the country over time, but formidable data collection problems would have to be confronted.

⁴⁶ Samuels (fn. 5).

⁴⁷ Wertman (fn. 25), 75.

⁴⁸ See the estimates in Katz, Richard S., “Preference Voting in Italy: Votes of Opinion, Belonging, or Exchange,” Comparative Political Studies 18 (July 1985), 233CrossRefGoogle Scholar, table 1.

⁴⁹ Gianfranco Pasquino, “Le radici del frazionismo e il voto di preferenza,” Rivista Italiana di Scienza Politico. 2 (August 1972).

⁵⁰ Zuckerman, Alan S., The Politics of Faction: Christian Democratic Rule in Italy (New Haven: Yale University Press, 1979), 111Google Scholar.

⁵¹ Sartori, Giovanni, “Proporzionalismo, frazionismo e crisi dei partiti,” Rivista Italiana di Scienza Politica 1 (December 1971)Google Scholar.

⁵² Reported by Mershon, Carol, The Costs of Competition (Stanford, Calif.: Stanford University Press, forthcoming.)Google Scholar

⁵³ Zuckerman (fn. 50), 67.

⁵⁴ Italy's smallest region, the Valle d'Aosta, was, because of its size, a single-member district that used a plurality system. Because intraparty competition did not occur there, the district is not included in the analysis reported below.

⁵⁵ For descriptions in English, see Barnes, Samuel H., Representation in Italy: Institutionalized Tradition andElectoral Choice (Chicago: University of Chicago Press, 1977), chap. 3Google Scholar; and Wertman (fn. 25).

⁵⁶ Districts electing sixteen or more representatives allowed a maximum of four preference votes to each elector; those electing fewer allowed three; reported in Barnes (fn. 55), 36.

⁵⁷ Katz, Richard S. and Bardi, Lucio, “Preference Voting and Turnover in Italian Parliamentary Elections,” American Journal of Political Science 24 (February 1980), 99CrossRefGoogle Scholar.

⁵⁸ For an analysis, see Pasquino, Gianfranco, “La preferenza unica: reazioni e opportunita,” in Pasquino, Gian-franco, ed., Votare un solo candidate: le consequenze politiche della preferenza unica (Bologna: II Mulino, 1993)Google Scholar.

⁵⁹ KatzandBardi(fn.57).

⁶⁰ Figures on preference votes have to be assembled and electronically input by hand, candidate by candidate, district by district, and election by election. “The volumes are available starting with La Navicella, IDeputati e Senatari delPrima Parlamento Repubblkano (Rome: La Navicella, 1948)Google Scholar.

⁶² There were exceptions to the rule that candidates receiving the most preference votes received parliamentary seats. Occasionally, a candidate died before taking his seat. More common was the phenomenon of standing in multiple districts, since Italian law permitted parliamentary candidates to stand in as many as three districts, as well as to run for both the Senate and the Chamber simultaneously. In these cases, candidates who received enough preference votes in different districts to win more than one parliamentary seat were required to select the district they would represent as well as the house in which they would be seated. Hence, there were instances in which a candidate who received enough preference votes to win a Chamber seat did not in fact subsequently take that seat, instead opting for another.

⁶³ Where necessary, we supplemented the information available in La Navicella with data from Pasquino, Gianfranco, ed., 1945—1996: archivio dellapolitica in Italia (Rome: Laterza Multimedia, CD Rom, 1996)Google Scholar.

⁶⁴ As far as we know, there is no standard measure of marginality in PR settings. This one seemed to us a reasonable approximation. Alternatives that occurred to us—such as the difference between the number of preference votes received by the highest- and second-highest-ranking DC candidates—captured intraparty competition more than interparty competition.

⁶⁵ Since multiple sets of charges may be lodged against the same individual deputy, where a single MP was charged more than once during the life of a single legislature, we dropped the multiple observations, thereby capping the number of RAP against a single MP at 1 for any legislature.

⁶⁶ Each measure of the variable INTER was constructed using each of the three lags discussed above, generating nine separate regressions. “Nathaniel Beck and Jonathan N. Katz, “What To Do (and Not To Do) with Time-Series Cross-Section Data,” American Political Science Review 89 (September 1995).

⁶⁸ Complete results are available from the authors upon request.

⁶⁹ To facilitate presentation, coefficient estimates for election-year dummy variables are not included; they are significant for every legislature starting in 1972 except 1976.

⁷⁰ Parisi, Arturo and Pasquino, Gianfranco, eds., Continuità e mutamento elettomle in Italia: le elezioni del20 giugno 1976 e ilsistemapolitico italiano (Bologna: II Mulino, 1977)Google Scholar; in English, see Parisi, Arturo and Pasquino, Gianfranco, “Changes in Italian Electoral Behavior: The Relationship between Parties and Voters,” in Lange, Peter and Tarrow, Sidney, eds., Italy in Transition: Conflict and Consensus (London: Frank Cass, 1980)Google Scholar.

⁷¹ In the results reported interparty competition is operationalized as the loss of the share of DC seats in the district at time t over t _-1 (model 2). The result for the first postwar election is therefore omitted, since there was no preceding election. While the other two models yield similar results, they are not presented to facilitate exposition. Complete results are available from the authors upon request.

⁷² Briefly stated, the Chow test works as follows. First, we set up a dummy variable, PERIOD, which equals 1 after 1972 (or 1976) and 0 otherwise. Then we create two interaction variables, PXINTER and PXINTRA, by taking the product of PERIOD and INTER and the product of PERIOD and INTRA. Finally, we examine whether the coefficients of PERIOD, PXINTER, and PXINTRA are jointly different from 0.

⁷³ Pizzorno (fn. 15).

⁷⁴ Because of difficulties in matching the records by name, we have not been able to combine our data sets listing the legislators charged with malfeasance with the data sets we compiled reporting the number of preference votes DC candidates received. We expect to do this in the future.

⁷⁵ Putnam, Robert, Making Democracy Work: Civic Traditions in Modern Italy (Princeton: Princeton University Press, 1993)Google Scholar.

⁷⁶ Most notably, Banfield, Edward C., The Moral Basis of a Backward Society (Glencoe, Ill.: Free Press, 1958)Google Scholar.

⁷⁷ Putnam (fn. 75), 96.

⁷⁸ Hine (fn. 16), 145.

⁷⁹ Ibid.

⁸⁰ This view turns on classing the Mafia as a cultural phenomenon, not an institution.

⁸¹ The intervening maps are not presented for reasons of space but are available from the authors upon request.

⁸² See Cazzola, Franco, “Partiti, correnti e voto di preferenza,” in Caciagli, Mario and Spreafico, Alberto, eds., Un sistema politico allaprova: studi sulle elezioni politkhe italiane del 1972 (Bologna: II Mulino, 1975), 143Google Scholar; and Schepis, Giovanni, “Analisi statistica dei risultati,” in Spreafico, Alberto and Palombara, Joseph La, eds., Elezioni e comportamento politico in Italia (Milan: Edizioni di Comunità, 1963), 376Google Scholar.

⁸³ Zuckerman (fn. 50), 110–11.

⁸⁴ In the III Legislature four southern districts were classed in the highest quartile of suspected malfeasance.

⁸⁵ Tarrow, Sidney, “Maintaining Hegemony in Italy: ‘The Softer They Rise, the Slower They Fall!’” in Pempel, T. J., ed., Uncommon Democracies: The One-Party Dominant Regimes (Ithaca, N.Y.: Cornell University Press, 1990)Google Scholar.

⁸⁶ We do not believe, however, that the end of communism was a significant cause in exposing Italian political corruption or in the collapse of the postwar party system; for a discussion, see Miriam A. Golden, “International Sources of the Collapse of Rent-Seeking Regimes: Hypotheses Drawn from the Italian Case” (Paper presented at the Joint Sessions of the European Consortium for Political Research, Grenoble, France, April 6–11, 2001).

⁸⁷ Given this, readers may wonder why the TI index for Italy did not show a substantial decline even at the turn of the millennium. The reason is that the TI index fails to distinguish bureaucratic from political corruption. In fact, since it is based on surveys of businesspeople, it may even reflect mainly bureaucratic corruption. We believe that bureaucratic corruption has remained relatively high in Italy (in part due to the absence of thoroughgoing reform of the public administration), whereas political corruption has fallen drastically since the change of regime in the mid-1990s. On the persistence of bureaucratic corruption, see Alberto Vannucci, “Inefficienza amministrative e corruzione,” Rivista Trimestrale di ScienzadellaAmministrazioneAA, no. 1 (1997).