The Goldwater Rule is a code of ethics that says that it's not okay for doctors or other mental health professionals to give opinions about political figures or public figures that they have not personally examined. It's kind of like when your teacher tells you that you can't say something about someone unless you have proof or know it is true. Mental health professionals need to know someone personally before they can say if they have a mental condition or not. This rule was named after a politician named Barry Goldwater who was talked about by mental health professionals who had never met him, which was unfair and not accurate. So, the Goldwater Rule was created to make sure this doesn't happen again and people are treated fairly.