Hours before the sun rose on Dallas police Chief Daniel Comeaux’s first day on the job, an elderly man in a wheelchair was shot dead near Fair Park. Two days later, the new chief stood among a cluster of officers outside the suspected gunman’s home in west Oak Cliff. He was impressed by one tool the investigators had used to arrive there: the network of license plate-reading cameras scattered across the city. “I was like, ‘Alright,’” Comeaux recalled saying, referencing the April case months later in an episode of Bridging the Divide, the Assist the Officer Foundation’s podcast, “‘explain this...