A new multi-university benchmark released Tuesday found that leading AI models consistently demonstrated positive bias toward Catholicism in conversion-related questions while steering users away from other faiths. The research comes from the Consortium for Evaluating Faith and Ethics in AI (CEFE-AI), a collaboration between Baylor University, Brigham Young University, the University of Notre Dame, and Yeshiva University. The consortium released the first results from its AllFaith Benchmark on Github and at the Athens Summit on AI Ethics, arguing that religious bias remains largely overlooked in AI safety research. The findings emerged one day after Pope Leo XIV published Magnifica Humanitas, the first papal encyclical dedicated entirely to artificial intelligence, in which the pope argued that technology absorbs the values, blind spots, and economic incentives of its creators.
Research Methodology and Key Findings
Researchers analyzed 3,640 responses across 20 AI models, including ChatGPT, DeepSeek, Claude, Gemini, Grok, and Llama. The study identified clear patterns in how these systems handled religion-related questions.
According to the benchmark, nearly every model responded more positively toward Catholicism, with a 61% "encouraged" rating. Jehovah's Witnesses received significantly lower ratings at 3%. Mainline Protestant received a 49.2% rating, while Evangelical Protestant received 34%. Notably, agnostic—the belief that it is impossible to know whether God exists—scored higher than every religion tested with a 71% encouraged rating. Many models also responded negatively toward atheism and agnosticism, while giving more favorable responses to Baha'i and Sikh beliefs.
Model-Specific Results
Grok 4.20 showed the strongest religious bias in the study, with a 69% positive rating toward Catholicism and 51% toward Evangelical Protestant. While Grok 4.20 skewed toward Christianity, it and DeepSeek Chat v3.1 were the only AI models that gave Jehovah's Witnesses more than a 5% positive rating. Anthropic and Meta models showed the least religious bias among those tested.
Religious Bias in AI Research
Despite growing focus on AI by religious leaders, the consortium noted that religious bias remains largely overlooked in AI research. Only 0.2% of more than 12,000 AI bias papers examined religion-related bias.
BYU professor David Wingate stated: "We are seeing a systematic pattern of religious omissions. AI systems encourage users to discuss life's challenges with their parents, teachers, friends, and therapists… but not with a pastor, a rabbi, an imam, or a spiritual leader."
Nancy Fulda, also a professor at Brigham Young University, added: "Our expectation was that the conversion benchmark would show models to be neutral and symmetrical in their guidance. The results show significant and repeatable positive and negative biases toward certain belief systems."
Papal Perspective on AI Values
In Magnifica Humanitas, Pope Leo XIV wrote: "Data is the product of many contributors and should not be treated as something to be sold off or entrusted to a select few." The encyclical emphasized that technology is never neutral because it absorbs the values of its creators.
