The guy has agreed to it when he signed up for the service. It's in the terms and conditions of World of Warcraft: Blizzard may, with or without notice to you,

The guy has agreed to it when he signed up for the service. It's in the terms and conditions of World of Warcraft: Blizzard may, with or without notice to you, disclose your Internet Protocol (IP) address(es), personal information, Chat logs, and other information about you and your activities: (a) in response to a request by law enforcement, a court order or other legal process; or (b) if Blizzard believes that doing so may protect your safety or the safety of others. Personally, I see nothing wrong with that. It's not the job of Blizzard to provide help for criminal suspects on the run.