Seeing Through Conflicts: Improving Instruction Hierarchy Alignment in Vision-Language Models

Nicholas Sansoterra, Zishuo Zheng, Sachin Kumar


Abstract
Instruction hierarchy (IH) alignment teaches language models to prioritize higher-level instructions when inputs conflict. While studied primarily in text-only settings, vision-language models (VLMs) introduce new challenges for IH: instructions may be embedded in images, split across modalities, visually transformed, or encountered during agentic tasks. Positing multimodal IH alignment as a reasoning problem, we train VLMs using reinforcement learning with rule-based rewards, comparing text-only, image-only, and mixed-modality supervision. We find that text-only IH training partially transfers to multimodal attacks, failing when models must decode, reconstruct, or reason over instructions across modalities. Image-based training improves robustness beyond text-only supervision, while mixed-modality training performs best overall. Importantly, the benefits generalize beyond the synthetic typographic training setting to real-image and web-agent safety tasks, while largely preserving general multimodal capability, showing that lightweight, verifiable supervision can meaningfully improve VLM robustness under adversarial, cross-modal, and interactive instruction conflicts
Anthology ID:
2026.findings-emnlp.1451
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2026
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
Findings
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
30912–30927
Language:
URL:
https://aclanthology.org/2026.findings-emnlp.1451/
DOI:
Bibkey:
Cite (ACL):
Nicholas Sansoterra, Zishuo Zheng, and Sachin Kumar. 2026. Seeing Through Conflicts: Improving Instruction Hierarchy Alignment in Vision-Language Models. In Findings of the Association for Computational Linguistics: EMNLP 2026, pages 30912–30927, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
Seeing Through Conflicts: Improving Instruction Hierarchy Alignment in Vision-Language Models (Sansoterra et al., Findings 2026)
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PDF:
https://aclanthology.org/2026.findings-emnlp.1451.pdf