Safety cameras. Web video streams. Cellphone towers.

Within the days after 4 school college students had been stabbed to dying of their Moscow, Idaho, rental house within the early hours of Nov. 13, police traced the digital footprint of the victims and the person accused of killing them in exhaustive element. 

Authorities tracked down the suspect’s automotive in his school parking zone, backtracked his cellphone’s actions for six months, and even discovered precisely what time one of many victims was utilizing TikTok on her cellphone, courtroom information present. They used a video stream from a meals truck to assist decide the place two of the victims had been earlier, and cellphone information to determine who gave them a journey house.

Whereas investigators labored lengthy hours to crack the case, expertise sped issues alongside dramatically, together with 1000’s of digital uploads processed by the FBI. With out a homicide weapon, motive or anybody seeing the killer’s face, authorities had been capable of make extraordinary use of developments in expertise to piece collectively the thriller surrounding who they are saying killed College of Idaho college students Ethan Chapin, 20, Madison Mogen, 21, Kaylee Goncalves, 21, and Xana Kernodle, 20 — an act of violence that upended the small school city.