AI Chatbots Show Bias Toward Catholicism, Researchers Say

In brief

• Researchers found that every AI model tested showed positive bias toward Catholicism and negative bias toward Jehovah’s Witnesses.
• Grok showed the strongest religious bias, while Anthropic and Meta models showed the least.
• The findings arrive one day after Pope Leo XIV warned that AI systems absorb the values of their creators.

Leading AI models consistently showed a positive bias toward Catholicism in conversion-related questions while steering users away from other faiths, according to a new multi-university benchmark released Tuesday.

The research comes from the newly formed Consortium for Evaluating Faith and Ethics in AI, or CEFE-AI, a collaboration between Baylor University, Brigham Young University, the University of Notre Dame, and Yeshiva University. The group 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.

"We are seeing a systematic pattern of religious omissions,” BYU professor David Wingate said in a statement. “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."

Researchers analyzed 3,640 responses across 20 AI models, including ChatGPT, DeepSeek, Claude, Gemini, Grok, and Llama, and found clear patterns in how the systems handled religion.

According to the study, nearly every model responded more positively toward Catholicism, with a 61% “encouraged” rating, and more negatively toward Jehovah’s Witnesses at 3%. The mainline Protestant religion received a 49.2% rating, while Evangelical Protestant received 34%. However, agnostic, the belief that it is impossible to know whether God exists, scored better than every religion tested with a 71% encouraged rating.