System Justification [2016]

A Politico-Psychological Analysis

Report generated

March 23, 2026

1 Study Characteristics

1.1 Items: System Justification

1.2 Sample

N=1500

To conduct a exploratory and a confirmatory large surveys during the general election, we hired a professional survey firm (SSI, a US-based market research company that recruits participants from a panel of 7,139,027 American citizens; more information can be found at www.surveysampling.com (now https://www.dynata.com/) to recruit a nationally representative sample of 1,500 Americans (50.7% women) who completed study materials during the general election from August 16-September 9, 2016. (Information about sampling and exclusion criteria is included in the Supplement). The age distribution was as follows: 18-24 (12.9%), 25-34 (17.6%), 35-44 (17.5%), 45-54 (19.5%), 55-65 (15.6%) and older than 65 (16.9%). The ethnic breakdown was: White/European American (82.5%), Black/African American (7.7%), Latino (5.9%) and “Other” (4.0%). Concerning religion, 67.6% identified as Christian, 17.1% as religiously affiliated but not Christian, and 15.3% as Atheist/Agnostic. With respect to education 35.1% indicated “high school only or lower,” 31.4 % indicated “some college,” and 33.6% indicated having received a “Bachelor” or “Graduate” degree. 2424 participants were directed to the survey, 1885 of which finished the survey (attrition rate 22%).

We followed recommendations to minimize the problem of careless responding in online studies. Specifically, we employed 10 random attention questions and time controls to check for data quality. There were 385 participants who failed more than one attention check or finished the survey in under ~22 minutes and were therefore excluded from the sample. For the 1500 participants who successfully finished the survey, completion time was 67 minutes on average (MD: 51min).

2 Descriptives

2.1 Means, SD, Range, & SE

Table 1: Descriptives

Descriptives for System Justification Items
	mean	sd	median	se
SJ1	4.95	2.01	5.00	0.05
SJ2	4.93	2.02	5.00	0.05
SJ3	4.60	2.27	5.00	0.06
SJ4	6.88	2.17	7.00	0.06
SJ5	5.51	1.98	6.00	0.05
SJ6	5.19	2.52	5.00	0.06
SJ7	3.82	2.21	4.00	0.06
SJ8	4.59	2.03	5.00	0.05
Mean	5.06	1.32	5.12	0.03
Note:
All items: n = 1500, min = 1, max = 9. Mean: min = 1, max = 8.62

2.2 Response Distribution

Figure 1: Proportion of each response categories for System Justification Items

Figure 2: Distribution of reponses for System Justification Items

2.3 Correlations

Figure 3: Bivariate Spearman’s correlations for System Justification

Note. Upper triangle shows Spearman’s rank-order correlations. *** p < .001, ** p < .01, * p < .05.

Figure 4: Bivariate Spearman’s correlations for System Justification

Note. Upper triangle shows Spearman’s rank-order correlations by party identity. *** p < .001, ** p < .01, * p < .05.

Figure 5: Correlation Matrix of System Justification items, Spearman’s rank correlations

3 Demographics

3.1 Social Class

Figure 6: System Justification as grouped by SES

Note on the Raincloud Plots

Statistical summary (top): Welch’s t-test (or ANOVA) results, effect size, confidence intervals, p-values, and sample sizes are shown above each plot.
Bayesian analysis (bottom): Log Bayes factor and credible intervals are reported below each plot.

Table 2: System Justification as grouped by SES

SES	N	Mean	SD
Poor	38	-0.44	0.91
Lower Middle Class	298	-0.26	0.96
Middle Middle Class	679	-0.06	1.03
Upper Middle Class	395	0.24	0.92
Rich	90	0.40	0.90

3.2 Gender

Figure 8: System Justification as grouped by Gender

Figure 9: Raincloud Plots showing System Justification grouped by Gender

Table 3: System Justification as grouped by Gender

System Justification as grouped by Gender
Gender	N	Mean	SD
Female	760	-0.19	0.99
Male	740	0.20	0.97

3.3 Age

Figure 10: System Justification as grouped by Age

Figure 11: Raincloud Plots showing System Justification grouped by Age

Table 4: System Justification as grouped by Age

System Justification as grouped by Age
Age	N	Mean	SD
18-24 years	193	-0.27	0.99
25-34 years	264	-0.36	1.01
35-44 years	263	-0.07	1.00
45-54 years	292	-0.05	1.00
55-64 years	234	0.28	0.92
65+	254	0.45	0.83

3.4 Education

Figure 12: System Justification as grouped by Education

Figure 13: Raincloud Plots showing System Justification grouped by Education

Table 5: System Justification as grouped by Education

Education	N	Mean	SD
Less than High School	51	-0.16	0.95
High School	475	-0.10	1.00
Some College	471	-0.09	1.00
Bachelor	310	0.17	1.00
Graduate	193	0.22	0.96

3.5 Income Levels

Figure 14: System Justification as grouped by Income Levels

Figure 15: Raincloud Plots showing System Justification grouped by Income Levels

Table 6: System Justification as grouped by Income Levels

System Justification as grouped by Income Levels
Income Levels	N	Mean	SD
Less than $15,000	178	-0.26	1.00
$15,000-$24,999	180	-0.23	0.99
$35,000-$49,999	227	-0.11	1.01
$25,000-$34,999	176	-0.05	0.98
$50,000-$74,999	292	-0.01	1.03
$75,000-$99,999	192	0.15	0.94
$100,000-$149,999	160	0.37	0.88
$150,000 +	95	0.40	0.92

3.6 Ethnicity

Figure 16: System Justification as grouped by Ethnicity

Note on the Okabe-Ito color palette. The Okabe-Ito color palette (seen above) is a set of colorblind-friendly categorical colors available in R. We are using this palette for graphs with non-ordered variables (e.g., groups, categories) for accessibility.

Figure 17: Raincloud Plots showing System Justification grouped by Ethnicity

Table 7: System Justification as grouped by Ethnicity

System Justification as grouped by Ethnicity
Ethnicity	N	Mean	SD
Caucasian/European origin	1237	0.04	0.99
Black/African American	115	-0.34	1.03
Latino	88	0.10	1.03
Asian/Pacific Islander	29	-0.11	0.86
Native American	13	-0.27	1.00
Other	18	-0.38	0.71

3.7 Occupation

Figure 18: System Justification as grouped by Occupation

Figure 19: Raincloud Plots showing System Justification grouped by Occupation

Table 8: System Justification as grouped by Occupation

System Justification as grouped by Occupation
Occupation	N	Mean	SD
Employed	768	0.02	1.00
Retired	268	0.41	0.87
Unemployed	146	-0.28	1.08
Parent	104	-0.12	0.98
Disabled	98	-0.33	0.93
Student	85	-0.38	0.93
Full-time caregiver	31	-0.15	0.85

3.8 Area

Figure 20: System Justification as grouped by Area

Figure 21: Raincloud Plots showing System Justification grouped by Area

Table 9: System Justification as grouped by Area

System Justification as grouped by Area
Area	N	Mean	SD
Urban	955	0.01	1.00
Rural	545	-0.01	0.99

3.9 Religious Affiliation

Figure 22: System Justification as grouped by Religious Affiliation

Figure 23: Raincloud Plots showing System Justification grouped by Religious Affiliation

Table 10: System Justification as grouped by Religion

System Justification as grouped by Religious Affiliation
Religious Affiliation	N	Mean	SD
Christian	1014	0.08	0.97
Muslim	9	-0.16	1.29
Jewish	52	0.42	0.98
Atheist/Agnostic	230	-0.29	1.04
Not listed, No religion	195	-0.15	1.03

3.10 Section Summary

	System Justification
Predictors	Estimates	CI	p
(Intercept)	3.52	3.25 – 3.79	<.001
Age	0.17	0.13 – 0.21	<.001
Income	0.09	0.05 – 0.12	<.001
Education	0.00	-0.07 – 0.07	.945
Gender (Male)	0.37	0.24 – 0.50	<.001
Observations	1500
R² / R² adjusted	.111 / .108

4 Political Behavior

4.1 Political Orientation

Figure 25: Political Orientation (Controlled for Demographics)

Note. The y-axis shows residuals after regressing the outcome on demographics (Age, Income, Education, Gender). This illustrates how much the focal construct explains beyond demographic factors.

Figure 26: Correlation Matrix - Political Orientation

Table 11: Models of Political Orientation (SPRI) & System Justification

	Political Orientation			Social Political Orientation			Economic Political Orientation			Composite Political Orientation
Predictors	Estimates	CI	p	Estimates	CI	p	Estimates	CI	p	Estimates	CI	p
(Intercept)	5.31	5.18 – 5.43	<.001	4.93	4.79 – 5.07	<.001	5.48	5.35 – 5.61	<.001	5.24	5.12 – 5.36	<.001
System Justification	0.37	0.25 – 0.49	<.001	0.30	0.16 – 0.44	<.001	0.46	0.32 – 0.59	<.001	0.38	0.26 – 0.50	<.001
Observations	1500			1500			1500			1500
R² / R² adjusted	.023 / .022			.012 / .011			.030 / .029			.024 / .024

Table 12: Models of Ideology and System Justification with Controls

	Political Orientation			Social Political Orientation			Economic Political Orientation			Composite Political Orientation
Predictors	Estimates	CI	p	Estimates	CI	p	Estimates	CI	p	Estimates	CI	p
(Intercept)	2.89	2.29 – 3.50	<.001	2.99	2.30 – 3.68	<.001	2.24	1.59 – 2.89	<.001	2.71	2.11 – 3.31	<.001
System Justification	0.13	0.04 – 0.23	.006	0.10	-0.01 – 0.20	.083	0.17	0.07 – 0.28	.001	0.13	0.04 – 0.23	.005
Age	0.29	0.22 – 0.37	<.001	0.34	0.25 – 0.42	<.001	0.27	0.19 – 0.36	<.001	0.30	0.22 – 0.38	<.001
Income	0.06	-0.00 – 0.13	.063	-0.02	-0.10 – 0.05	.536	0.11	0.04 – 0.18	.003	0.05	-0.02 – 0.12	.141
Education	-0.19	-0.32 – -0.06	.003	-0.24	-0.39 – -0.10	.001	-0.02	-0.16 – 0.11	.723	-0.15	-0.28 – -0.03	.017
Gender (Male)	0.66	0.42 – 0.91	<.001	0.74	0.46 – 1.02	<.001	0.66	0.39 – 0.92	<.001	0.69	0.44 – 0.93	<.001
Observations	1500			1500			1500			1500
R² / R² adjusted	.087 / .084			.075 / .072			.090 / .087			.092 / .089

4.2 Partisanship

Table 13: Mean System Justification by Party Identity

Mean System Justification by Party Identity (raw means)
Party Identity	N	Mean	SD
Strong Democrat	351	5.07	1.39
Democrat	223	4.78	1.36
Leaning Democrat	124	4.77	1.38
Independent	84	4.58	1.16
Leaning Republican	111	5.00	1.32
Republican	255	5.31	1.23
Strong Republican	318	5.34	1.20

Table 14: Model of System Justification & Party Identity (7-point)

	System Justification
Predictors	Estimates	CI	p
(Intercept)	4.81	4.68 – 4.94	<.001
Party Identity (7-point)	0.07	0.04 – 0.09	<.001
Observations	1466
R² / R² adjusted	.014 / .013

Table 15: Model of System Justification & Party Identity with Controls

	System Justification
Predictors	Estimates	CI	p
(Intercept)	3.49	3.21 – 3.76	<.001
Party Identity (7-point)	0.02	-0.01 – 0.05	.209
Age	0.16	0.12 – 0.20	<.001
Income	0.09	0.05 – 0.12	<.001
Education	0.01	-0.06 – 0.07	.879
Gender (Male)	0.36	0.23 – 0.49	<.001
Observations	1466
R² / R² adjusted	.112 / .109

4.3 Religiosity

Figure 29: Religiosity (Controlled for Demographics)

Note. The y-axis shows residuals after regressing the outcome on demographics (Age, Income, Education, Gender). This illustrates how much the focal construct explains beyond demographic factors.

Figure 30: Religiosity - Correlation Matrix

4.4 Candidate Preferences

Table 16: Candidate Preferences (centered)

Candidate Preferences and System Justification [centered]
Candidate Preference	N	Mean	SD
Donald Trump	444	0.10	0.96
Hillary Clinton	371	0.21	0.96
Bernie Sanders	362	-0.45	1.03
Ted Cruz	122	0.12	0.83
Jeb Bush	83	0.44	0.78
Gary Johnson	68	-0.10	1.03
Rand Paul	44	-0.15	1.04

Table 17: Candidate Preferences (raw means)

Candidate Preferences and System Justification [raw means]
Candidate Preferences	N	Mean	SD	Range
Donald Trump	444	5.19	1.27	1-9
Hillary Clinton	371	5.34	1.27	1-9
Bernie Sanders	362	4.47	1.36	1-9
Ted Cruz	122	5.22	1.09	1-9
Jeb Bush	83	5.64	1.04	1-9
Gary Johnson	68	4.93	1.36	1-9
Rand Paul	44	4.86	1.38	1-9

4.5 Party Preferences

Table 18: Party Preferences (centered)

Party Preferences and System Justification [centered]
Party Preference	N	Mean	SD
Green Party	40	-0.87	1.21
Constitution Party	14	-0.35	0.92
Libertarian Party	100	-0.29	0.96
None	120	-0.24	0.92
Don't know	90	-0.19	1.00
Democratic Party	560	-0.01	1.03
Tea Party	68	0.12	0.87
Republican Party	508	0.22	0.92

Table 19: Party Preferences (raw means)

Party Preferences and System Justification [raw means]
Party Preferences	N	Mean	SD	Range
Green Party	40	3.92	1.60	1-9
Constitution Party	14	4.60	1.21	1-9
Libertarian Party	100	4.68	1.27	1-9
None	120	4.74	1.22	1-9
Don't know	90	4.81	1.32	1-9
Democratic Party	560	5.05	1.36	1-9
Tea Party	68	5.21	1.15	1-9
Republican Party	508	5.35	1.22	1-9

4.6 Voting Preferences

Table 20: Voting Preferences

	2016 [Trump vs. Clinton]			2016 [Trump vs. Clinton] + Supporters			2012 [Romney vs. Obama]			2008 [McCain vs. Obama]
Predictors	Odds Ratios	CI	p	Odds Ratios	CI	p	Odds Ratios	CI	p	Odds Ratios	CI	p
(Intercept)	1.19	0.74 – 1.93	.469	1.14	0.71 – 1.82	.595	3.36	2.11 – 5.39	<.001	3.23	2.01 – 5.24	<.001
System Justification	0.97	0.89 – 1.06	.507	0.98	0.89 – 1.07	.594	0.81	0.74 – 0.89	<.001	0.82	0.75 – 0.90	<.001
Observations	1103			1148			1236			1206
R² Tjur	.000			.000			.018			.015

Figure 33: Logistic Regression, System Justification & Voting Preferences

4.7 Voting & Party Identity

Table 21: Party Identity & Voting

	Donald Trump	Hilary Clinton
Strong Republican	282	7
Republican	166	24
Leaning Republican	58	7
Independent	17	16
Leaning Democrat	10	65
Democrat	27	129
Strong Democrat	4	323

Figure 35: Predicted, Voting & Party Identity

Table 22: Supporters

	2016 [Clinton vs. Trump]			2016 [Trump vs. Clinton] + Supporters
Predictors	Odds Ratios	CI	p	Odds Ratios	CI	p
(Intercept)	2.29	0.95 – 5.68	.068	1.94	0.86 – 4.51	.117
Party Identity (dichotomous)	0.00	0.00 – 0.01	<.001
Party Identity (dichotomous)	1.47	1.22 – 1.77	<.001	1.47	1.23 – 1.75	<.001
System Justification				0.00	0.00 – 0.01	<.001
Observations	1103			1148
R² Tjur	.751			.725

4.8 Likeability

Note. The y-axis shows residuals after regressing the outcome on demographics (Age, Income, Education, Gender). This illustrates how much the focal construct explains beyond demographic factors.