In January 2025, a 17-year-old opened fire in his school cafeteria, killing a teenage girl before turning the gun on himself. In the aftermath, Matt Kriner faces a different kind of investigation. His job is to dig through the suspect’s vast digital footprint, a record rife with racist and violent rhetoric, and piece together not just what happened, but why. And what it might take to prevent it from happening again.

Matt Kriner has a background in intelligence analysis and is the Executive Director Institute for Countering Digital Extremism (ICDE), which he co-founded to provide guidance to government agencies and tech companies helping prevent online radicalization and offline extremist harms. Matt is the expert witness for several key legal cases against accelerationist perpetrators in both the U.S. and Canada, and his insights may be found in a variety of outlets, including the PBS Documentary The Rise and Fall of Terrorgram.