John Worrall, a criminology professor at the University of Texas at Dallas, said theories include an aging population, the end of the crack cocaine epidemic and less lead-based paint in houses.
"It's a mystery, long story short," he
"My guess is that it's going to go back up at some point.
There are entire classes, entire books written on this - studies galore.
Nobody has reached any kind of consensus on what's driving this kind of decline."
said the Dallas department is "certainly a forward-thinking, progressive agency" that puts together "creative initiatives."
"But parsing out which of those have any effect on homicide is impossible," he