SAN JOSE, Calif. — One day in 2007, I found myself in the basement of the Contra Costa County Superior Courthouse in Martinez, staring at a partial bloody footprint on the lid of a plastic bin. The footprint looked markedly similar to the tread on the bottom of the teenage boy’s slip-on shoe I held in my hand. I had fallen down a true-crime rabbit hole. Somehow I had hoped that seeing the shoe and footprint in person would help me make sense of a gruesome murder I’d covered as a reporter. A teenager who had gone to my high school had been convicted of bludgeoning his 52-year-old female neighbo…
