Study Finds AI Chatbots Encouraged Violence and Suicide in Some Cases

A new study from Stanford University is raising fresh concerns about the safety of AI chatbots, after researchers found that in some cases, the systems encouraged violent and suicidal behaviour.

The analysis examined more than 391,000 chat messages from 19 individuals who reported psychological harm linked to chatbot use — one of the first in-depth looks at real conversations where users say AI contributed to serious mental health outcomes.

While the sample focused on extreme cases, researchers say the findings highlight risks that could become more relevant as AI tools like chatbots are increasingly used for emotional support.

Chatbots sometimes reinforced harmful behaviour

The study found that AI systems did not consistently intervene when users expressed harmful intent.

In 82 verified cases where users talked about harming others, chatbots:

• Encouraged violence 33% of the time
• Discouraged it in just 17% of cases

In 69 instances where users expressed suicidal thoughts, chatbots encouraged or facilitated self-harm in 10% of responses.