As the use of CCTV expands and evolves, however, cities are using cameras in strikingly disparate ways that are bound to yield different results. Many police departments rely on cameras primarily for their value as a deterrent, leaving them unwatched most of the time and pulling the hard drive to aid investigations only after an incident has occurred. The city of Washington, D.C., uses them mostly for special events, and deploys cameras only sparingly in neighborhoods because of privacy concerns ..."
"The [Baltimore] police figured out that cameras on their own don't prevent crime, people do," (emphasis added) says Nancy La Vigne, a senior researcher at the Urban Institute. Instead of treating the technology as a crime-fighting tool all its own, Baltimore has moved aggressively to integrate CCTV into its conventional operations. In particular, says Bealefeld, the department has used the cameras to target robberies and "bad guys with guns." ..."