Program Goals/Program Components
Public surveillance systems include a network of cameras and components for monitoring, recording, and transmitting video images. These systems are typically equipped with night vision, color recording, and have the ability to pan, tilt, and zoom. Most cameras are pre-programmed to scan an area for a predetermined time and pattern, yet can also be operated remotely by security personnel or an automated computer system to focus on a particular area of interest.
In 2000, officials in the city of Baltimore, Md., were committed to using technology and data to positively impact the crime rate in their city. City officials envisioned a similar system in Baltimore that was already widespread in other major metropolitans (such as London, England and Chicago, Ill.) and were confident that such a system could help reduce the historically high levels of crime, specifically violent crime.
Prior to the implementation of public surveillance cameras, Baltimore experienced 11,183 violent crimes and 48,653 total crimes, resulting in the seventh-highest violent crime rate and 28th overall highest crime rate in the United States (La Vigne et al. 2011). Public surveillance cameras offered the opportunity to use technology that could aid in the prevention, detection, and investigation of these crimes.
Public surveillance systems are grounded in the theory that potential offenders will be less inclined to commit criminal activity in the presence of cameras that are recording activity, as this would place them at greater risk for apprehension. Furthermore, proponents of public surveillance systems also believe that such systems have the ability to increase perceptions of safety among citizens, as well as encourage citizens to utilize public spaces that are now guarded by surveillance (La Vigne et al. 2011). By increasing the number of citizens utilizing public spaces, more individuals can potentially serve as witnesses to crimes, presenting the possibility of greater crime reduction. Additionally, video footage of a crime may also help in investigations and prosecutions.
With the ultimate goal of crime reduction, cameras were placed throughout the city of Baltimore in areas with the highest crime rates. Installation areas included the 50-block downtown area and other selected neighborhoods. Crime rates were determined by incident and arrest reports, as well as input from district commanders. Overall these areas had a disproportionate number of shootings, murders and assaults, and were known for drug use. The selected areas were assessed to determine the feasibility of camera installation within the existing environment, which resulted in the installation of light poles to support the cameras, as well as the trimming of trees to ensure the camera’s range was not obstructed.
Furthermore, necessary precautions were taken to ensure that the cameras did not infringe on the civil liberties of community members. An individualized range of motion for each camera was set to capture the desired images. Cameras were designed to follow their individualized pattern for 24 hours, moving from right to left and zooming in on desired locations. A variety of Baltimore Police officers, including retired officers, also have the ability to monitor the cameras, selecting the specific areas they want to focus on within the camera’s range. Given their experience, these officers were aware of crime hot spots, persistent offenders, and specific body language to suggest the occurrence of a crime.
Civilians can also function as monitors with the proper training. All monitors must pass a criminal background check and a drug test. After passing these tests all monitors are given a manual which outlines the specifics of monitoring, such as activities that can and cannot be monitored.
Overall, La Vigne and colleagues (2011) found that the implementation of public surveillance cameras has a positive effect on crime reduction, as three of the four selected areas in Baltimore, Md., experienced significant declines in crime rates following camera installment.
Total Crime in Downtown Baltimore
The time series analysis showed that camera implementation in the downtown area had a positive impact on crime rates. Following camera implementation in in May 2005, the total monthly crime rate (including all seven crime categories of analysis) decreased by more than 10 incidents each month. A statistically significant impact was found beginning in the fourth month following camera implementation; total crime decreased by 25 percent.
Total Crime in the Greenmount Area
When comparing pre/post-intervention crime rates in Greenmount to the matched comparison area for the same time periods, the results showed an average of eight fewer incidents per month in the Greenmount area, resulting in a statistically significant 20 percent crime reduction as a result of the public surveillance cameras' implementation.
Total Crime in the North Avenue Area
When comparing pre/post-intervention crime rates in the North Avenue area to those in the matched comparison area, only a slight non-significant decrease was found.
Total Crime in the Tri-District Area
When comparing pre/post-intervention crime rates in the Tri-District area to the matched comparison area for the same time periods, the results showed an average of 12 fewer incidents per month in the Tri-District area, resulting in a statistically significant 25 percent crime reduction as a result of the public surveillance cameras' implementation.