Use of social network websites in investigations

Social network services are increasingly being used in legal and criminal investigations. Information posted on sites such as Twitter, Instagram, and Facebook has been used by police and university officials to prosecute users of said sites. In some situations, content posted on Myspace has been used in court to determine an appropriate sentence based on a defendant's attitude.

The U.S. DOT National Highway Traffic Safety Administration (NHTSA) has made federal grants available to states to train law enforcement officers to use social media sites to identify events that may result in impaired driving or consumption by minors. As of 2012, Michigan spent over $4.5 million through this program, and has trained over 100 local police officers to use social media sites to identify and target events. In more recent years, a majority of police departments have some sort of social media-based strategy in place.

Social media can be used as an investigative tool to obtain probable cause for a search warrant. Agencies can surveil social media sites via software programs, such as X1 Social Discovery, MediaSonar, and Geofeedia.