Before he opened fire on the Florida State University campus last year, killing two people and wounding six others, Phoenix Ikner had a conversation.

Not with a friend, a parent or anyone who might have talked him out of it—but with an AI chatbot.

According to evidence gathered by Florida’s attorney general, the student had asked ChatGPT which weapon and ammunition would be best suited for his attack, and when and where he could inflict the most casualties.

The chatbot, investigators say, answered his questions.