We will share personal information with companies, organizations or individuals outside of Google if we have a good-faith belief that access, use, preservation or disclosure of the information is reasonably necessary to:
...
protect against harm to the rights, property or safety of Google ,our users or the public as required or permitted by law.
https://mail.google.com/mail/help/intl/en/terms.html
However I read very quickly so please correct me if I'm wrong.