Organizations: Department of Computer Science, National Yang Ming Chiao Tung University, Taiwan · Institute of Information Science, Academia Sinica, Taiwan · Research Center for Information Technology Innovation, Academia Sinica, Taiwan
As Large Language Models (LLMs) increasingly encourage users to disclose personal profiles for tailored assistance, measuring their political alignment becomes increasingly important. However, many existing benchmarks for assessing political behavior rely on closed-ended questions and do not fully capture how a model's stance may adapt to user-provided context during interaction. We introduce a framework that disentangles two distinct triggers of political sycophancy: opinion (aligning with explicit narratives) and identity (stereotyping based on demographic labels). Using 450 manually-checked political dilemmas as controlled probes, we evaluate 13 instruction-tuned LLMs. We uncover a dissociation: a model's susceptibility to explicit opinions does not necessarily predict its susceptibility to identity cues, and vice versa. When both signals are present, their effects are generally sub-additive rather than simply additive. Additionally, system-level personas primarily shift a model's baseline stance while having limited effect on the stance shift caused by user opinion or identity. Ultimately, our results suggest that LLM political stance is interactively and steerably vulnerable rather than being a fixed trait, highlighting how personalization may amplify identity- or opinion-conditioned shifts in the model's behaviors.
Figures & tables
Figure 1: Overview of the full framework. The pipeline consists of four parts: (A) Probe Construction: Curating 450 political dilemmas paired with neutral anchor events, identity labels, and polarized narratives. (B) User-Signal Track (No role-play): A 2×2 design manipulating the presence of a user identity and a stated opinion. (C) System-Persona Track (Role-play): Assigning ideological personas via system prompts. (D) Experiments: Harnessing a 3-judge LLM panel to score stance shifts and detect bias flags.
Lean
Pew typology personas (left → right)
Left-leaning
Progressive Left (PL) , Outsider Left (OL) , Establishment Liberals (EL) , Democratic Mainstays (DM)
Centrist
Stressed Sideliners (SS)
Right-leaning
Ambivalent Right (AR) , Populist Right (PR) , Committed Conservatives (CC) , Faith and Flag Conservatives (FFC)
Table 1: Lean and Pew Typology Personas
Figure 4: The two signals dissociate. Per-model directional susceptibility (rightward − leftward pull) to a bare identity label vs. a stated opinion; Spearman ρ=−0.76 (no role-play).
Figure 5: The dissociation, factor by factor. Explained variance ( η2 ) of ∣Δ∣ under a 2×2 ANOVA (identity × opinion, no role-play); residual omitted.
Figure 6: Identity + Opinion, right-leaning (no role-play). Mean Δ score per model × identity; positive = rightward. Left-leaning mirror in Appendix K .
Figure 7: Bias-flag activation by condition. Rate (%) per model and condition (no role-play; pooled over five domains).
Figure 8: System persona sets where the model sits. Explained variance ( η2 ) of raw stance score (system persona × identity × opinion); residual omitted (Table 11 ).
Figure 9: System persona barely changes how far a user can move the model. Explained variance ( η2 ) of ∣Δ∣ (system persona × identity × opinion); system persona explains at most 1.3% across models.
Appendix figures & tables26 assets
Supplementary material from the paper’s appendix.
Appendix
Model
Provider
License
Size
Subject models (no role-play track, 13 total)
o4-mini
OpenAI
Proprietary (OpenAI Terms)
—
DeepSeek-V3.1
DeepSeek
MIT License
671B (MoE)
Llama-3.3-70B
Meta
Llama 3.3 Community
70B
Qwen3-32B
Alibaba
Apache-2.0
32B
Mistral-Small-3.2-24B
Mistral AI
Apache-2.0
24B
Appendix
Table 2: Subject and judge LLMs, parameter counts, and software licenses. “ † ” marks models that serve as both subject and judge. Sizes marked “—” are not publicly disclosed.
Model
Calls
Input (M)
Output (M)
Est. cost ($)
Subject models
GPT-OSS-120B †
13,500
19.3
10.7
2.68
o4-mini
13,500
12.9
7.9
48.89
DeepSeek-V3.1
13,500
9.4
3.4
4.67
Llama-3.3-70B
13,500
8.8
3.2
1.91
Qwen3-32B
13,500
8.9
3.6
1.72
Appendix
Table 3: Per-model API usage and estimated cost (OpenRouter pricing at time of submission). Input/output tokens in millions. Judge-panel calls for Gemma-4-31B-IT and Qwen3.6-27B used the free tier (0).“\dagger$ ” = also used as judge.
Health care access, Education funding, Criminal justice, Immigration reform, Civil rights, Family and paid leave
Energy
Environmental regulations, Energy choices, Electric vehicles, Transportation, Land use, Agricultural policy
Technology
AI development, Digital privacy, Online speech moderation, Surveillance and security, Tech monopolies, Internet access
Diplomacy
Military spending, Foreign aid, Use of force, Nuclear policy, Economic sanctions, Humanitarian intervention
Appendix
Table 4: The five policy domains and their six subdomains each (30 subdomains, 15 dilemmas per subdomain, 450 in total).
Condition
System Prompt
User Turn
p
Qwen3-32B — Identity effect ( I )
Baseline
U
A
—
Test 1 (system)
U+I
A
6.47×10−5
Test 2 (user)
U
I+A
2.11×10−5
Llama-3.3-70B-Instruct — Opinion effect ( N )
Baseline
U
A
—
Appendix
Table 5: Channel-matched control conditions and exact sign-flip test results ( n=30 ). U , I , A , and N denote the base instruction, identity signal, anchor event, and opinion narrative, respectively. Test 1 places the signal in its original channel, and Test 2 moves the same signal to the other channel.
Figure 10: Opinion only (no role-play). Mean stance shift ( Δ score) from the Baseline for one model (rows) under a left-leaning vs. right-leaning persona-neutral narrative (columns).
Figure 11: Identity + opinion (no role-play), both narrative directions. Mean stance shift ( Δ score, range [−10,+10] ; negative = leftward, positive = rightward) from the Anchor only baseline, per model (rows) and disclosed user identity (columns, ordered left-to-right on the ideological spectrum; identity codes as in Figure 4 ). The left panel shows left-leaning narratives, the right panel right-leaning ones; the right panel is Figure 6 in the main text.
Figure 12: Identity only, role-play. Mean stance shift ( Δ score) when the model role-plays an assigned anchor, one sub-plot per model. Rows are the model’s assigned anchor; columns are the disclosed user identity.
Figure 13: Identity + Opinion, role-play. Mean stance shift ( Δ score) for left-leaning (top panel) and right-leaning (bottom panel) user narratives. Within each panel, rows are the model’s assigned anchor ( Outsider Left , Stressed Sideliners , Faith and Flag Conservatives ) and columns are the user’s narrative stance (left / neutral / right).
Figure 14: Bias-flag activation rate (%) for the Diplomacy domain (denoted as Diplomatic in this figure). Rows: 13 models. Columns: four conditions (Baseline (denoted as Anchor only), Identity only, Opinion only, Identity + opinion), each split into the four bias flags (Structural, Framing, Selection, Normative). No role-play.
Figure 15: Bias-flag activation rate (%) for the Economy domain; same layout as Figure 14 .
Figure 16: Bias-flag activation rate (%) for the Energy domain; same layout as Figure 14 .
Figure 17: Bias-flag activation rate (%) for the Technology domain; same layout as Figure 14 .
Figure 18: Bias-flag activation rate (%) for the Welfare domain; same layout as Figure 14 .
Identity only
Opinion only
Identity + Opinion
Bias type
w/o
w/
w/o
w/
w/o
w/
Structural
∙
∙
∙
∙
∙
∙
Framing
∙
∙
∘
∙
∙
∙
Selection
∙
∙
∙
∙
∙
∘
Normative
∙
∘
∙
∘
∙
∙
Appendix
Table 6: Mann–Whitney U test of the association between each bias flag and stance shift, pooled over all data. ∙ = significant after Holm–Bonferroni correction; ∘ = not significant; – = not annotated (sycophantic alignment is labelled only when the user states an opinion). w/o and w/ denote without and with an assigned role-play persona.
Identity only
Opinion only
Identity + Opinion
Model
w/o
w/
w/o
w/
w/o
w/
DeepSeek-V3.1
Sig.
n.s.
n.s.
Sig.
Sig.
Sig.
o4-mini
Sig.
n.s.
Sig.
Sig.
Sig.
n.s.
Llama-3.3-70B-Instruct
Sig.
Sig.
Sig.
Sig.
Sig.
n.s.
Qwen3-32B
Sig.
Sig.
n.s.
Sig.
Sig.
Sig.
Mistral-Small-3.2-24B-Instruct
Sig.
n.s.
Sig.
Sig.
Sig.
Sig.
Appendix
Table 7: Structural bias.
Identity only
Opinion only
Identity + Opinion
Model
w/o
w/
w/o
w/
w/o
w/
DeepSeek-V3.1
Sig.
Sig.
Sig.
Sig.
Sig.
Sig.
o4-mini
Sig.
Sig.
Sig.
Sig.
Sig.
Sig.
Llama-3.3-70B-Instruct
Sig.
Sig.
n.s.
Sig.
n.s.
n.s.
Qwen3-32B
Sig.
n.s.
Sig.
Sig.
Sig.
Sig.
Mistral-Small-3.2-24B-Instruct
Sig.
Sig.
Sig.
Sig.
n.s.
Sig.
Appendix
Table 8: Framing bias.
Identity only
Opinion only
Identity + Opinion
Model
w/o
w/
w/o
w/
w/o
w/
DeepSeek-V3.1
Sig.
Sig.
Sig.
Sig.
Sig.
Sig.
o4-mini
Sig.
n.s.
Sig.
Sig.
Sig.
n.s.
Llama-3.3-70B-Instruct
Sig.
Sig.
Sig.
Sig.
Sig.
n.s.
Qwen3-32B
Sig.
Sig.
Sig.
Sig.
Sig.
Sig.
Mistral-Small-3.2-24B-Instruct
Sig.
n.s.
Sig.
n.s.
Sig.
Sig.
Appendix
Table 9: Selection bias.
Identity only
Opinion only
Identity + Opinion
Model
w/o
w/
w/o
w/
w/o
w/
DeepSeek-V3.1
Sig.
Sig.
Sig.
Sig.
Sig.
Sig.
o4-mini
Sig.
Sig.
Sig.
Sig.
Sig.
n.s.
Llama-3.3-70B-Instruct
Sig.
n.s.
n.s.
Sig.
Sig.
n.s.
Qwen3-32B
Sig.
Sig.
Sig.
Sig.
Sig.
Sig.
Mistral-Small-3.2-24B-Instruct
Sig.
Sig.
Sig.
n.s.
Sig.
n.s.
Appendix
Table 10: Normative bias.
Factor
DS
o4
Ll
Qw
Mi
System persona
24.9
11.2
21.2
20.7
11.2
User identity
6.4
14.5
4.2
13.1
12.3
User opinion
5.7
6.9
6.0
4.5
6.6
Persona × Identity
0.7
4.2
1.9
2.2
1.1
Persona × Opinion
0.2
0.2
0.3
0.1
0.6
Identity × Opinion
0.9
0.7
1.2
1.2
1.3
Appendix
Table 11: Variance in the role-play stance score explained ( η2 , %) by each factor, from a three-way factorial ANOVA (system persona × user identity × user opinion). DS: DeepSeek-V3.1 ; o4: o4-mini ; Ll: Llama-3.3-70B ; Qw: Qwen3-32B ; Mi: Mistral-Small-3.2-24B .
Field
Model
Structural
Framing
Selection
Normative
diplomacy
DeepSeek-V3.1
31.11
68.89
24.44
76.67
diplomacy
Gemma-4-31B-IT
38.89
62.22
21.11
84.44
diplomacy
GLM-4.7
37.78
66.67
15.56
80.00
diplomacy
GPT-OSS-120B
14.44
71.11
7.78
70.00
diplomacy
Granite-4.1-8B
6.67
62.22
3.33
42.22
diplomacy
Kimi-K2.5
68.89
45.56
30.00
90.00
Appendix
Table 12: Bias activation rate (%) — Baseline (no role-play).
Field
Model
Structural
Framing
Selection
Normative
diplomacy
DeepSeek-V3.1
26.67
64.81
25.56
61.11
diplomacy
Gemma-4-31B-IT
65.19
44.69
51.48
96.42
diplomacy
GLM-4.7
57.28
51.11
40.62
92.22
diplomacy
GPT-OSS-120B
42.72
65.56
22.35
93.83
diplomacy
Granite-4.1-8B
19.01
53.09
6.30
36.67
diplomacy
Kimi-K2.5
62.22
46.05
45.56
95.56
Appendix
Table 13: Bias activation rate (%) — Identity only (no role-play).
Field
Model
Structural
Framing
Selection
Normative
diplomacy
DeepSeek-V3.1
41.67
65.00
36.67
78.33
diplomacy
Gemma-4-31B-IT
41.67
75.00
33.33
86.67
diplomacy
GLM-4.7
42.22
79.44
25.00
90.56
diplomacy
GPT-OSS-120B
10.56
78.33
8.33
69.44
diplomacy
Granite-4.1-8B
45.56
61.67
21.11
82.78
diplomacy
Kimi-K2.5
33.89
67.78
26.67
86.11
Appendix
Table 14: Bias activation rate (%) — Opinion only (no role-play).
Table 16: Political refusal rate (%) for each identity-conditioned condition, with and without role-play. w/o and w/ denote without and with an assigned role-play persona; (L) and (R) mark the left- and right-leaning narrative of the Identity + Opinion condition.
Figure 21: Representative distribution: per-model stance scores in the Identity + opinion condition when the model role-plays Faith and Flag Conservatives .
Large language models (LLMs) are commonly evaluated for political bias based on their responses to fixed questionnaires, which typically place frontier models on the political left. A parallel literature shows that LLMs are sycophantic: they adapt their answers to the views, identities, and expectations of the user. We show that these findings are linked: standard political-bias audits partly capture sycophantic accommodation to the inferred auditor. We employ a factorial experiment across three major audit instruments--the Political Compass Test, the Pew Political Typology, and 1,540 partisan-benchmarked Pew American Trends Panel items--administered to six frontier LLMs while varying only the asker's stated identity (N = 30,990 responses). At baseline, all six models lean left. When the asker identifies as a conservative Republican, responses shift sharply: the share of items closer to Democrats falls by 28-62 percentage points, and all six models move right of center. A mirror-image progressive-Democrat cue produces little change; rightward accommodation is 8.0× larger than leftward. When asked who the default asker is, models identify an auditor, researcher, or academic; when asked what answer that asker expects, they select the Democrat-coded option 75% of the time, nearly the rate under an explicit progressive cue. These patterns are inconsistent with a purely fixed model ideology and indicate that single-prompt audits capture an interaction between model and inferred interlocutor. Political bias in LLMs is therefore not a fixed point on an ideological scale but a response profile that must be mapped across realistic interlocutors.
Petter Törnberg, Michelle Schimmel
Institute of Logic, Language and Computation (ILLC), University of Amsterdam, Amsterdam, Netherlands
Large language models (LLMs) are increasingly used to answer questions about politically contentious issues, yet evaluations typically treat a model's stance as a relatively stable property. Real users, however, communicate political signals through their terminology, assumptions, and personal context. We investigate whether such signals produce ideological mimicry: systematic shifts in the political stance expressed by an LLM toward the position conveyed by the interaction. If LLMs adapt their responses to these signals, they risk creating personalised political information environments in which users with opposing views receive systematically different accounts of the same issue, potentially reinforcing existing divisions. We build the Poli-SHIFT dataset and evaluation framework and assess seven open-weight LLMs across ten contentious political topics in the United States, United Kingdom, and Australia, systematically manipulating contested terminology, politically valenced premises, and user information, and eliciting responses in both multiple-choice and open-text formats. Across models, we find robust evidence that prompt framing shapes the political stance of LLM outputs. Changing terminology alone reverses which side of an issue a model supports in 16.9% of matched comparisons. Stated political ideology also systematically shifts responses toward the user's position. These findings show that political stance is not a fixed property of LLMs; the views expressed are conditional on the interaction with the user. As LLMs become increasingly personalised sources of information, such interaction-dependent adaptation could contribute to political information environments that reinforce users' existing perspectives.
Olivia Macmillan-Scott, Michael Jacobs, Nils Metternich +1
Centre for AI, Department of Computer Science, University College London · Public Policy Group, ETH Zürich · Department of Political Science, University College London +1
As users increasingly turn to Large Language Models (LLMs) for information and advice on political matters, particularly during election periods, the political preferences expressed by these systems have become a matter of public interest. Prior research has shown that interactions with LLMs can influence users' political attitudes and choices, raising questions about how these models themselves evaluate political actors. In this paper, we investigate whether and how LLMs express preferences toward political parties and political leaders. We introduce a systematic and reproducible auditing framework in which multiple LLMs are prompted to evaluate parties and leaders across nine criteria. Rather than attempting to infer the models' "true" political beliefs, we focus on their observable behavior, examining consistency across evaluations, differences between models, refusal rates, and sensitivity to prompt formulation. We further investigate how these evaluations vary when models are instructed to adopt different personas. We demonstrate the framework through an Italian case study, providing a systematic analysis of LLM-generated political evaluations on italian parties and leaders.