1 Weston H. Agor, The Chilean Senate: Internal Distribution of Influence (Austin, 1971), pp. 6–36; Jorge Tapia Valdes, La técnica legislativa (Santiago, 1960), pp. 40–3; Arturo Valenzuela, The Breakdown of Democratic Regimes: Chile (Baltimore, 1978); Arturo Valenzuela and Alexander Wilde, ‘Presidential Politics and the Decline of the Chilean Congress’, in Joel Smith and Lloyd D. Musolf (eds.), Legislatures in Development: Dynamics of Change in New and Old States (Durham, 1979); Federico Gil, The Political System of Chile (Boston, 1966), pp. 117–18.

2 Gil, The Political System of Chile, p. 121.

3 Goldberg, Peter, ‘The Politics of Allende and the Overthrow in Chile’, Political Science Quarterly, vol. 90, no. 1 (1975), pp. 93–116Google Scholar; Videla, Jorge Tapia, ‘The Chilean Presidency in a Developmental Perspective’, Journal of Interamerican Studies and World Affairs, vol. 19, no. 4 (1977), pp. 451–81.Google Scholar

4 Tomás Pablo Elorza, El Congreso Nacional visto desde su Presidencia (Santiago, 1971), p. 56.

5 Valenzuela and Wilde, ‘Presidential Politics’; Matthew S. Shugart and John M. Carey, Presidents and Assemblies: Constitutional Design and Electoral Dynamics (Cambridge, 1992).

6 Mainwaring, Scott, ‘Presidentialism in Latin America’, Latin America Research Review, vol. 25, no. 1 (1990), pp. 157–79Google Scholar; Shugart and Carey, Presidents and Assemblies, pp. 35–7; Peter Siavelis, The President and Congress in Postauthoritarian Chile (University Park PA, 2000), p. 142; Ames, Barry, ‘The Congressional Connection: The Structure of Politics and the Distribution of Public Expenditures in Brazil's Competitive Period’, Comparative Politics, vol. 19, no. 2 (1987), pp. 147–71Google Scholar; Verónica Montecinos, ‘Economic Policy Making and Parliamentary Accountability in Chile’, Democracy, Governance and Human Rights Program Paper 11, United Nations Research Institute for Social Development, 2003.

7 Brian Loveman, Struggle in the Countryside: Politics and Rural Labor in Chile, 1919–1973 (Bloomington, 1976); Robert R. Kaufman, The Politics of Land Reform in Chile, 1950–1970 (Cambridge, 1972); Barbara Stallings, Class Conflict and Economic Development in Chile, 1958–1973 (Stanford, 1978).

8 Valenzuela, The Breakdown of Democratic Regimes.

9 Valenzuela and Wilde, ‘Presidential Politics’.

10 Ibid.

11 Germán Urzúa Valenzuela, Historia política de Chile y su evolución electoral: Desde 1810 a 1992 (Santiago, 1992).

12 Valenzuela, The Breakdown of Democratic Regimes, p. 18.

13 Valenzuela and Wilde, ‘Presidential Politics’, p. 201.

14 Legislators could not increase expenditures, create new public services or set wages in the public sector. However, they could still reassign items during the amendment process to help fund pet projects. As a result, spending bills sent by the executive were frequently changed as they travelled towards enactment. As conservative senator Francisco Bulnes noted, some of the limitations established by the reform of 1943 were also circumvented by allowing congressional initiatives to set wages in the private sector, which in turn forced readjustments in the public sector. Cited in Enrique Brahm Garcia, Raúl Bertelsen Repetto and Andrés Amunátegui Echeverría, Régimen de gobierno en Chile: ¿Presidencialismo o parlamentarismo? 1925–1973 (Santiago, 2002), p. 180.

15 Prior to the 1970s, the authority to declare that an amendment was not relevant to the bill in question rested with the president of the chamber. Former president of the senate Pablo Elorza recognised the pressures felt by chamber authorities when confronted by these types of amendments, and admitted that traditionally the chamber president would ask the plenary whether a motion was appropriate so as to not risk his position, ‘and in doing so [the chamber's president] se lavaba las manos’. Pablo Elorza, El Congreso Nacional visto desde su Presidencia, p. 47.

16 Valenzuela and Wilde, ‘Presidential Politics’.

17 As to why the DC pushed for constitutional reforms that presumably strengthened executive discretion when it was unsure about winning the following presidential contest, three points should be noted. First, the reforms also included key provisions that strengthened checks and balances such as an independent Constitutional Tribunal, and the use of plebiscites to resolve some inter-branch disagreement on constitutional matters. Second, reforms that strengthened executive authority over spending bills and halted omnibus bills tended to hurt legislators from the traditional parties, who often engaged in particularistic exchanges – much more than DC legislators, who came to office campaigning to end those discredited logrolls. Third, those executive actions that would become controversial and eventually deeply polarising under the Allende government, such as the expropriation of factories by decree, would be legally justified not by the discretion provided by the 1970 reforms but by some arcane provisions introduced in 1932 (agricultural expropriations would be carried on under new interpretations of existing agrarian reform laws).

18 Valenzuela and Wilde, ‘Presidential Politics’, pp. 209–10.

19 Mainwaring, ‘Presidentialism in Latin America’, pp. 157–79.

20 Shugart and Carey, Presidents and Assemblies, pp. 35–7.

21 Ibid., p. 200.

22 Obler, Jeffrey, ‘Legislatures and the Survival of Political Systems: A Review Article’, Political Science Quarterly, vol. 96, no. 1 (1981), pp. 127–39.CrossRefGoogle Scholar

23 Timothy Scully, Rethinking the Center: Party Politics in Nineteenth and Twentieth Century Chile (Stanford, 1992); Julio Faundez, Marxism and Democracy in Chile (New Haven, 1988), p. 314.

24 Tapia Videla, ‘The Chilean Presidency in a Developmental Perspective,’ p. 466.

25 Ibid.

26 Pablo Elorza, El Congreso Nacional visto desde su Presidencia, p. 56.

27 Women were allowed to vote in municipal elections after the constitutional reform of 1934.

28 This reform also prohibited local electoral alliances and gave national party organisations a monopoly over the direction of electoral coalitions. Scully, Rethinking the Center, p. 134; Shugart and Carey, Presidents and Assemblies, p. 199.

29 As a result of these institutional reforms and other demographic changes, the electorate expanded from about 630,000 in 1946 to 4.51 million in 1973.

30 The rural bias in the electoral law also made rural constituencies more attractive and intensified competition among the different parties. See Scully, Rethinking the Center, p. 153.

31 Federico Gil and Charles J. Parrish, The Chilean Presidential Election of September 4, 1964 (Washington DC, 1965), p. 25.

32 Garretón, Manuel Antonio, ‘Chile: En búsqueda de la democracia perdida’, Desarrollo Económico, vol. 25, no. 99 (1985), pp. 381–97.Google Scholar

33 Faundez, Marxism and Democracy in Chile, p. 242.

34 Ibid., pp. 125–6; Scully, Rethinking the Center, pp. 163–4.

35 Faundez, Marxism and Democracy in Chile, p. 126.

36 Brian Loveman, Chile: The Legacy of Hispanic Capitalism (Oxford, 2001), p. 235.

37 Cited in Stallings, Class Conflict and Economic Development in Chile, p. 95.

38 Scully, Rethinking the Center, p. 163.

39 At this time, the two major parties of the left, the Socialist and Communist parties, had solidified their vision of a Marxist-Leninist path of transformation towards socialism, even if they would disagree about the most appropriate methods to achieve it. See Garretón, ‘Chile: en búsqueda de la democracia perdida’.

40 Genaro Arriagada Herrera, De la via chilena a la via insurreccional (Santiago, 1974), p. 72.

41 Julio Cesar Jobet, El Partido Socialista de Chile (Santiago, 1971) vol. 2, p. 130.

42 Arriagada Herrera, De la via chilena a la via insurreccional, p. 75; Faundez, Marxism and Democracy in Chile, p. 226. The process of radicalisation also included small splinters from the major parties, such as MAPU and Izquierda Cristiana, small parties built by former DC members that eventually joined the Popular Unity coalition backing the government of Salvador Allende.

43 Loveman, Chile: The Legacy of Hispanic Capitalism, pp. 244–5; Arturo Valenzuela, ‘Chile’, in Juan J. Linz and Alfred Stepan (eds.), The Breakdown of Democratic Regimes (Baltimore, 1978), pp. 53–4, 62–3.

44 Valenzuela, ‘Chile’, pp. 68–9; Loveman, Chile: The Legacy of Hispanic Capitalism, pp. 248–9; James F. Petras, ‘Nationalization, Socioeconomic Change and Popular Participation’, in Arturo Valenzuela and J. Samuel Valenzuela (eds.), Chile: Politics and Society (New Jersey, 1976).

45 The dependent variable in this argument is congressional decay (i.e., the weakening of congressional ties and cross-partisan consensus-seeking behaviour), and this rival explanation does not presuppose a direct connection between this outcome and the coup of 1973, as Shugart and Carey do in their interpretation of Valenzuela and Wilde's argument. There were multiple factors contributing to the breakdown of democracy, including many unrelated to congressional politics or executive–legislative relations – economic factors, foreign influence, military politics and so forth.

46 Valenzuela and Wilde, ‘Presidential Politics’; Shugart and Carey, Presidents and Assemblies.

47 Navia, Patricio, ‘La transformación de votos en escaños: Leyes electorales en Chile, 1833–2004’, Política y Gobierno, vol. 12, no. 2 (2005), pp. 233–76.Google Scholar

48 Siavelis, Peter, ‘Continuity and Change in the Chilean Party System’, Comparative Political Studies, vol. 30, no. 6 (1997), pp 651–74Google Scholar; Guzmán, Eugenio, ‘Reflexiones sobre el sistema binominal’, Estudios Públicos, no. 51 (1993), pp. 303–25Google Scholar; Rabkin, Rhoda, ‘Redemocratization, Electoral Engineering, and Party Strategies in Chile, 1989–1995,’ Comparative Political Studies, vol. 29, no. 3 (1996), pp. 335–56.Google Scholar

49 Time helped to reduce the uncertainties over whether the ideological repositioning was genuine, as did stabilising patterns of electoral competition.

50 Valenzuela and Wilde, ‘Presidential Politics’.

51 NetDraw software was used for this figure. Stephen P Borgatti, Netdraw Network Visualization (Harvard MA, 2002).

52 In social network terminology this is called an ‘egonet’.

53 Ucinet software was used for this analysis. Stephen P Borgatti, M. G. Everett and L. C. Freeman, Ucinet for Windows: Software for Social Network Analysis (Harvard MA, 2002).

54 The process of generating these standard errors involves sampling with replacement from the vertices of the affiliation matrix (sociomatrix). A sociomatrix is an adjacency matrix, or a so-called one-mode network where a column and a row exist for each actor and entries indicate the tie between two actors. Snijders, Tom A. B. and Borgatti, Stephen P., ‘Non-Parametric Standard Errors and Tests for Network Statistics’, Connections, vol. 22, no. 2 (1999), pp. 161–70.Google Scholar

55 Stanley Wasserman and Katherine Faust, Social Network Analysis: Methods and Applications (New York, 2006), p. 254.

56 It also includes a few legislators from other leftist organisations such as PADENA in 1961–65.

57 The dependent variable is the log of degree plus one.

58 The Radical Party and DC are grouped together for this analysis.