https://www.theverge.com/2019/8/5/20754761/trump-social-media-companies-mass... “I am directing the Department of Justice to work in partnership with local state and federal agencies, as well as social media companies, to develop tools that can detect mass shooters before they strike,” Trump said in the speech. While the president did not specify what those “tools” might look like, Trump seemed to be suggesting that companies could use predictive software to single out potential shooters based on their activity on a platform. Crucially, this would mean taking action before a person commits violent crimes. Data-mining tools are in wide use, but creating a detection system for violence would inevitably raise a host of privacy and accountability issues.