The police began using social media almost by accident, he says. One officer discovered over the course of ordinary social media use that he could see the status updates of neighborhood kids. Soon, cops and prosecutors were looking at photos to figure out who might be a witness in a particular case. Bystanders could be identified from the background of photos posted on social media sites. If a kid posted a time-stamped photo of himself standing in front of a door, and the cop recognized the doorway, it could be relevant in an investigation.
Today, police across the country regularly use social media data to keep tabs on citizens. 75 percent of them are self-taught, according to a 2014 Lexis-Nexis research report on social media use in law enforcement. “Facebook has helped me by identifying suspects that were friends or associates of other suspects in a crime and all brought in and interviewed and later convicted of theft and drug offenses,” said one respondent interviewed in the report. “My biggest use for social media has been to locate and identify criminals,” said another. “I have started to utilize it to piece together local drug networks.” Only 9 percent of respondents had received training on using social media in investigations from their agency.
Social media can produce evidence in some cases, but it also fails to capture the complexity of human relationships—and can sometimes distort them. For this reason, it is important to take care that social media data is not misused or misinterpreted in the pursuit of justice.