https://www.theverge.com/2018/9/28/17915902/facebook-messenger-protected-us-government-wiretap-requests

A US District Court judge in California has ruled in favor of Facebook, denying a joint federal and state task force that tried to force the social networking company to wiretap Messenger voice calls by holding the company in contempt of court, according to a report from Reuters.

The case first came up last month, when the Department of Justice was reportedly looking to hold Facebook in contempt of court for refusing to comply with a wiretapping request for an ongoing investigation into the MS-13 gang. Because Messenger calls are conducted over a cellular data connection or Wi-Fi, they are not subject to the same wiretap laws as standard phone calls, which law enforcement can gain access to with a proper warrant.