SANCTUARY: An Efficient Evidence-based Automated Fact Checking System

Arbaaz Dharmavaram, Saqib Hakak


Abstract
With the growing volume of misinformation online, automated fact-checking systems are becoming increasingly important. This paper presents SANCTUARY, an efficient pipeline for evidence-based verification of real-world claims. Our approach consists of three stages: Hypothetical Question & Passage Generation, a two-step Retrieval-Augmented Generation (RAG) hybrid evidence retrieval, and structured reasoning and prediction, which leverages two lightweight Large Language Models (LLMs). On the challenging AVeriTeC benchmark, our system achieves 25.27 points on the new AVeriTeC score (Ev2R recall), outperforming the previous state-of-the-art baseline by 5 absolute points (1.25× relative improvement). Sanctuary demonstrates that careful retrieval, reasoning strategies and well-integrated language models can substantially advance automated fact-checking performance.
Anthology ID:
2025.fever-1.19
Volume:
Proceedings of the Eighth Fact Extraction and VERification Workshop (FEVER)
Month:
July
Year:
2025
Address:
Vienna, Austria
Editors:
Mubashara Akhtar, Rami Aly, Christos Christodoulopoulos, Oana Cocarascu, Zhijiang Guo, Arpit Mittal, Michael Schlichtkrull, James Thorne, Andreas Vlachos
Venues:
FEVER | WS
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
247–257
Language:
URL:
https://preview.aclanthology.org/mtsummit-25-ingestion/2025.fever-1.19/
DOI:
10.18653/v1/2025.fever-1.19
Bibkey:
Cite (ACL):
Arbaaz Dharmavaram and Saqib Hakak. 2025. SANCTUARY: An Efficient Evidence-based Automated Fact Checking System. In Proceedings of the Eighth Fact Extraction and VERification Workshop (FEVER), pages 247–257, Vienna, Austria. Association for Computational Linguistics.
Cite (Informal):
SANCTUARY: An Efficient Evidence-based Automated Fact Checking System (Dharmavaram & Hakak, FEVER 2025)
Copy Citation:
PDF:
https://preview.aclanthology.org/mtsummit-25-ingestion/2025.fever-1.19.pdf