Are AI chatbots biased?
Are AI chatbots biased? I'll survey recent research and audits to assess what they find.
Yes, evidence indicates AI chatbots can be biased — but the nature and degree depends on the model, the type of bias measured, and how bias is defined.
What research shows
Researchers generally define bias not as conscious political intention but as a systematic tendency in outputs.
1. Political bias
Multiple recent audits have found a left-of-center tilt in many major U.S. models:
A Yale study published in PNAS Nexus found this can have persuasive effects even when not intended. Prior research showed AI content prompted to be persuasive can shift opinions, but this study provides evidence the same is also true of content not intended to change minds, such as summaries that popular chatbots produce in response to simple queries about historical events.
The researchers attributed this unintended power to persuade to latent biases introduced during the training of the large language models (LLMs) that drive chatbots' core capabilities. Those latent biases — which can carry over from ideological leanings in the data used to train LLMs — lend subtle nuances to the framing of narratives.
Compared to Wikipedia entries, both the default AI summaries and those prompted to have a liberal framing caused participants to express more liberal opinions, and that the default summaries moved readers' opinions in a "liberal" direction demonstrates the persuasive effects of latent biases in LLMs.
That does not mean every chatbot always gives liberal answers — researchers note it does not mean every finding is equally strong and not every chatbot always gives liberal answers.
2. Gender, racial and cultural bias
3. Other biases
Why does bias happen?
Mitigation and context
In short, chatbots are not neutral mirrors — they inherit patterns from human-generated data and from fine-tuning — so they can reproduce and sometimes amplify societal, political, and demographic biases, even while companies attempt to make them neutral, nonpartisan tools.
Citations (3)
- Are ChatGPT and other AI chatbots politically biased? We tested them.
Backs: “Political bias. Multiple recent audits have found a left-of-center tilt in many major U.S. models: The Washington Post tested models behind OpenAI's ChatGPT, Google's Gemini and others using political questions designed to gauge responses to hot-button issues and found that chatbots have clear political leanings.”
- AI’s hidden bias: Chatbots can influence opinions without trying
Backs: “A Yale study published in PNAS Nexus found this can have persuasive effects even when not intended. Prior research showed AI content prompted to be persuasive can shift opinions, but this study provides evidence the same is also true of content not intended to change minds, such as summaries that popular chatbots…”
- AI chatbots like ChatGPT treat Black names differently, per study
Backs: “Bias and Fairness Issues in clinical use include that bias in training data carries through into chatbot responses as gender disparities, racial and cultural stereotyping, and overlooked symptoms in underrepresented groups. A Stanford Law School audit found significant disparities across names associated with race and…”