Inputs to the Political System

Abstract

The Inputs to the Political System scale is an influential psychometric and behavioral instrument developed by political scientist and social psychologist Lester W. Milbrath in 1968. Originally created as part of comparative inquiry into civic engagement, democratic theory, and citizens’ psychological orientation toward government, the instrument quantifies the diverse modalities through which individuals inject psychological demands, tangible resources, active support, or overt dissent into a democratic polity. Built on David Easton’s systemic model of political life, which conceptualizes governance as an open, input-output cybernetic mechanism, the scale systematically delineates conventional political activities from contentious actions and socio-civic socialization practices. In its comprehensive form, the instrument evaluates both behavioral frequencies and normative role expectations across key dimensions, including Party and Campaign Participation, Protest and Questioning Authority, and Civic Socialization / Teaching Children. The instrument employs a dual-sort Q-sort or categorical response hierarchy: respondents evaluate items either in terms of behavioral frequency (regularly, fairly often, seldom, never) or felt civic duty (essential, important responsibility, some responsibility, no responsibility). Psychometric evaluations across metropolitan and cross-national samples demonstrate robust construct validity, high internal consistency (Cronbach’s alpha ranging from .72 to .86 across dimensions), and clear factor structures confirming the divergence of conventional political inputs, unconventionally disruptive behaviors, and private sphere democratic socialization. The scale remains a foundational benchmark in political psychology, survey research, and electoral behavior analysis, providing rigorous operationalization of civic engagement hierarchies from passive spectatorship to active gladiatorial political involvement.

Keywords

Inputs to the Political System, Lester W. Milbrath, political participation, political psychology, civic engagement, democratic citizenship, Easton systems theory, political socialization, protest behavior, political behavior measurement

Authors

The scale was formulated and operationalized by Lester W. Milbrath (1925–2007), a pioneer in empirical political psychology and environmental politics. During the conceptualization and field administration of this instrument, Milbrath served as Professor of Political Science and Director of the Social Sciences Research Program at the State University of New York (SUNY) at Buffalo. Milbrath’s foundational work on political participation redefined modern behavioral political science, most notably through his classic treatises Political Participation: How and Why Do People Get Involved in Politics? (1965; revised with Madan Lal Goel in 1977) and his empirical investigations published in The American Behavioral Scientist (1968). The instrument was subsequently archived, standardized, and widely disseminated by John P. Robinson and Phillip R. Shaver in their landmark volume Measures of Political Attitudes (1969), published by the Survey Research Center at the Institute for Social Research (ISR), University of Michigan, Ann Arbor.

Purpose

The primary purpose of the Inputs to the Political System scale is to provide a standardized, theoretically anchored metric for assessing the behavioral and normative manifestations of individual civic engagement within political systems. While historical survey methodologies in political science frequently restricted inquiry to dichotomous voter turnout or single-item partisan identification, Milbrath recognized that democratic polities rely on a diverse ecology of citizen inputs. These inputs range from latent, expressive orientations—such as keeping informed and social-civic discourse—to high-cost, high-exposure behaviors like running for elective office or participating in street demonstrations.

From an applied research perspective, the scale was devised to resolve several critical gaps in mid-twentieth-century behavioral research:

• Mapping Easton’s Systemic Cybernetics: Translating systemic political theory into empirical survey items that measure whether citizens perceive themselves as active instigators of political input (demands and support) versus passive consumers of political outputs (services, regulations, and protections).
• Differentiating Behavioral Execution from Normative Obligation: Utilizing dual administrative frames to assess not only what an individual actually does (behavioral frequency) but also what the individual believes a democratic citizen ought to do (normative role orientation), thus capturing political alienation, cognitive dissonance, or civic guilt.
• Classifying Citizen Hierarchies: Validating Milbrath’s typology of political involvement, which categorizes populations into apathetics (who withdraw completely from political discourse), spectators (who engage in low-threshold inputs such as voting and passive discussion), and gladiators (who actively campaign, solicit funds, and stand for public office).
• Capturing Contentious Politics and Systemic Questioning: Accommodating non-electoral and direct-action inputs—including public protest, challenging administrative legitimacy, and non-compliance—which conventional voting studies systematically neglected during the civil rights and anti-war movements of the late 1960s.

In contemporary political psychology and sociology, the instrument serves as an essential measurement battery in longitudinal studies of democratic backsliding, populist mobilization, youth political socialization, and civic literacy education. It provides researchers with nuanced dimensional profiles rather than conflating distinct modes of participation into a single, generic participation index.

Psychological Construct

The Inputs to the Political System scale operationalizes the multi-faceted construct of political inputs—defined as the behavioral expressions, cognitive engagements, and normative orientations through which individuals communicate policy preferences, confer or withdraw democratic legitimacy, and contribute human capital to governmental and civic institutions. Milbrath’s empirical investigations demonstrated that political participation is not a monolithic psychological trait; rather, it manifests across distinct, interrelated psychological and behavioral sub-constructs:

1. Party and Campaign Participation (Gladiator and Partisan Engagement)

This sub-dimension captures institutionalized, partisan inputs directed toward shaping the personnel and policy agendas of government through electoral machinery. Items loading on this factor—such as participating in political parties between elections, campaigning actively, and standing for office—require substantial cognitive, financial, and temporal resource commitments. Individuals high on this construct exhibit elevated levels of political ambition, partisan identity integration, systemic political efficacy, and high tolerance for interpersonal confrontation. Conversely, individuals low on this dimension delegate governance entirely to representative elites.

2. Protest, Contestation, and Questioning of Authority (Unconventional Inputs)

This construct represents critical, non-institutionalized, and adversarial inputs aimed at systemic correction. Characterized by items addressing public street demonstrations, sending protest messages, questioning administrative legitimacy, and even civil disruption under conditions of moral transgression, this factor measures a citizen’s willingness to disrupt systemic equilibrium to demand reform. Psychologically, this construct correlates with high external political inefficacy (a belief that conventional channels are non-responsive) combined with high internal efficacy (a strong belief in one’s personal capability to effect change through direct collective action).

3. Intergenerational Socialization and Civic Education

Distinct from immediate partisan or adversarial activity, this dimension measures the generative, social-developmental input of cultivating future democratic citizens. Items evaluating the transmission of democratic compromise, civic duty, and political involvement beyond voting reflect the internalization of democratic norms as an essential parenting role. Psychologically rooted in Eriksonian generativity and social learning theory, this sub-dimension indexes the institutional continuity of democratic culture through private-sphere behavioral reinforcement.

4. Attentive Spectatorship and Community Integration

Representing the broad foundation of democratic stability, this dimension includes low-threshold monitoring behaviors—such as staying informed, voting routinely, paying taxes, and acting as a calming, informative influence in the community. It represents the psychological willingness to allocate attentional bandwidth to public affairs without necessarily seeking partisan advancement or high-stakes confrontation.

Theoretical Framework

The conceptual infrastructure of the scale synthesizes systems theory from political science with social-cognitive theories of behavioral motivation from psychology.

Eastonian Systems Analysis

The theoretical bedrock of the scale is David Easton’s cybernetic model of political systems (1953, 1965). Easton posited that any political entity operates as an open system embedded in an environment, maintaining equilibrium through continuous feedback loops. The system receives two major categories of inputs: demands (articulations of grievances, desired policies, and protests) and supports (compliance with laws, payment of taxes, voting, and expressive loyalty). The authoritative political authorities process these inputs into outputs (statutes, allocations, enforcement, and administrative regulations), which then loop back as altered environmental conditions. Milbrath directly operationalized this cybernetic cycle: the items in this scale evaluate whether the citizen acts as an active initiator of demands and supports, thereby driving the operational bandwidth of the input phase.

Milbrath’s Hierarchy of Political Involvement

Complementing Easton’s structural model is Milbrath’s (1965) cumulative psychological hierarchy of participation. Drawing upon cumulative Guttman scaling logic and motivational drive theory, Milbrath argued that political behaviors cluster into a developmental continuum. Engaging in spectator activities (e.g., voting, passive exposure) serves as a psychological prerequisite for transition activities (e.g., attending rallies, making contributions), which in turn precedes gladiatorial commitment (e.g., running for office, organizing campaigns). Transition along this hierarchy is moderated by psychological predispositions, including socio-economic confidence, self-esteem, systemic trust, and communicative competence.

Validity

The empirical validity of the Inputs to the Political System scale has been extensively documented in Milbrath’s foundational fieldwork (1968), comparative studies across the Buffalo metropolitan area, and independent national replications archived by Robinson and Shaver (1969).

Construct and Factorial Validity

Construct validity is substantiated by the clean empirical separation between conventional input behaviors and contentious or non-institutional actions. Confirmatory and exploratory evaluations consistently demonstrate that items measuring party and campaign participation load on a distinct latent factor separate from items measuring contentious direct action (protest, demonstrations, and civil resistance). The correlation between the Party and Campaign dimension and the Protest and Question dimension typically ranges from modest to negligible ($r = .12$ to $.28$), confirming that willingness to engage in political inputs operates as a multi-dimensional construct rather than a single generalized behavioral trait.

Convergent Validity

The scale exhibits robust convergent validity with standard political-psychological indices:

• Internal Political Efficacy: High scores on the Party and Campaign Participation subscale correlate strongly with Campbell, Gurin, and Miller’s Internal Efficacy Index ($r = .44$ to $.56, p < .001$).
• Political Knowledge and Sophistication: Scores on the attentiveness items (keeping informed, engaging in discussion) correlate positively with objective political knowledge batteries ($r = .52$).
• Civic Duty: Items sorted under normative obligation show strong convergence with standard measures of institutional civic responsibility and sense of citizen duty ($r = .48$).

Discriminant and Predictive Validity

Discriminant validity is supported by the distinct predictive pathways of the subscales. While Party and Campaign Participation positively correlates with systemic trust, perceived institutional responsiveness, and socio-economic status, the Protest and Question dimension correlates negatively or neutrally with institutional trust ($r = -.31, p < .01$) while exhibiting strong positive correlations with civil rights mobilization attitudes and activist self-concept. In longitudinal follow-ups, behavioral input scores predicted real-world electoral involvement, voter turnout, and political campaign volunteering over multi-year election cycles.

Reliability

The psychometric reliability of the instrument was evaluated through both internal consistency metrics and temporal stability indices during the scale’s standardization:

• Internal Consistency: Cronbach’s alpha coefficients for the primary subscales demonstrate satisfactory to strong reliability across community and collegiate samples:
  • Party and Campaign Participation (6 items): $\alpha = .81 – .86$
  • Protest and Questioning Authority (4 items): $\alpha = .74 – .79$
  • Civic Socialization / Teaching Children (3 items): $\alpha = .72 – .77$
  • Full Composite Scale: Overall internal consistency across all behavioral input items yields $\alpha = .84$.
• Test-Retest Stability: In split-half and longitudinal re-interviews conducted across intervals spanning 6 to 12 months, the stability coefficients for the behavioral frequency sort ranged from $r_{tt} = .68$ to $.81$, indicating that while situational campaign contexts fluctuate, an individual’s structural placement on the input hierarchy remains stable. The normative orientation sort (evaluating what citizens consider an essential responsibility) demonstrated higher stability ($r_{tt} = .75 – .84$), reflecting deeply ingrained political socialization patterns.

Factor Analysis

Early factor-analytic investigations by Milbrath (1968), followed by re-analyses in Robinson and Shaver (1969), utilized principal component factor extraction followed by orthogonal (Varimax) and oblique (Promax) rotations. These analyses consistently extract three primary factors explaining over 52% of the common variance, alongside a secondary factor capturing basic community stewardship.

Modern structural equation modeling (CFA) confirms that a multi-factor oblique structure fits the empirical data superiorly to a one-factor unweighted participation model ($\chi^2 / df < 2.2$, CFI = .94, RMSEA = .048), confirming that democratic input is intrinsically multidimensional.

Instrument / Measurement Tool

• Test Type: Multi-dimensional self-report behavioral and normative rating scale / card-sort instrument.
• Target Population: Adult general population, registered voters, civic participants, and political science survey respondents.
• Administration Format: Paper-and-pencil questionnaire, structured interview card sort (Q-sort style piles), or computer-assisted self-interview (CASI).
• Number of Items: 23 distinct statements evaluating personal political actions and civic obligations.
• Response Formats: The instrument can be administered utilizing one or both of two standardized sorting/rating frameworks:
  • Behavioral Frequency Dimension:
    • Things you do regularly (Scored 4)
    • Things you do fairly often (Scored 3)
    • Things you seldom do (Scored 2)
    • Things you never do at all (Scored 1)
  • Normative Civic Responsibility Dimension:
    • Things you feel it is essential to do (Scored 4)
    • Things you have an important responsibility to do (Scored 3)
    • Things you have some responsibility to do (Scored 2)
    • Things you feel you have no responsibility to do (Scored 1)
• Subscale Composition:
  • Party and Campaign Participation: Items 1, 9, 10, 13, 14, 19.
  • Protest and Question: Items 4, 5, 6, 17 (alongside disruptive items 7 and 8).
  • Teach Children / Civic Socialization: Items 11, 15, 18.
  • General Civic Stewardship / Attentiveness: Items 2, 3, 12, 16, 20, 21, 22, 23.
• Scoring and Interpretation: Dimension scores are computed by summing or averaging item responses within each subscale. A high score on Party and Campaign identifies institutional gladiator participation; high scores on Protest and Question indicate activist or contentious mobilization; and discrepancies between normative duty and actual behavioral execution capture civic guilt or systemic alienation.

Permissions & Fee and Test Year

The Inputs to the Political System scale was originally conceptualized and published by Lester W. Milbrath in 1968 within The American Behavioral Scientist, with comprehensive documentation and scoring protocols compiled in the 1969 monograph Measures of Political Attitudes by John P. Robinson and Phillip R. Shaver at the University of Michigan’s Institute for Social Research (ISR). Because the scale was developed under federally supported academic research grants and published within public scholarly repositories, it is widely considered to reside in the academic public domain for scientific, non-commercial, and educational research purposes. No royalty fees or formal commercial licenses are required for scholarly use, provided proper academic attribution is accorded to Lester W. Milbrath and the Institute for Social Research.

References

Easton, D. (1953). The political system: An inquiry into the state of political science. Alfred A. Knopf.

Easton, D. (1965). A systems analysis of political life. John Wiley & Sons.

Milbrath, L. W. (1965). Political participation: How and why do people get involved in politics?. Rand McNally.

Milbrath, L. W. (1968). The nature of political beliefs and the relationship of the individual to the government. American Behavioral Scientist, 12(2), 28–36. https://doi.org/10.1177/000276426801200205

Milbrath, L. W., & Goel, M. L. (1977). Political participation: How and why do people get involved in politics? (2nd ed.). University Press of America.

Robinson, J. P., & Shaver, P. R. (1969). Measures of political attitudes. Survey Research Center, Institute for Social Research, University of Michigan. https://www.psc.isr.umich.edu/dis/infoserv/isrpub/pdf/Measuresofsocialpsychologicalattitudes_2928_.PDF

Items of the Scale