History

• According to the Institute for Law and Justice, the first CAD system was used in 1965 by the St. Louis, Missouri Police Department. The impact on department communications was so successful that by the mid-80s almost all medium-sized departments to large-sized agencies had adopted the use of a CAD system.
  
  

Function

• When utilized by a police department dispatch center, a CAD system functions as both a data entry and a data retrieval system. When a call comes in a dispatcher uses CAD to log the call, including the pertinent information given by the caller, such as type of crime, suspect and victims. The dispatcher will then send officers to the call and will update the log entry through CAD as events occur. Some examples of specific events would be time of arrival, suspect arrest and the final disposition of the call. During the call the dispatcher may also query several law enforcement databases through the CAD program. In these instances, the CAD program will attach the query and its results to the open call for service.
  
  

Features

• Two types of CAD systems are in use today: those that function on DOS command prompts and those that utilize a Windows graphic interface. All systems allow for logging calls and information; facilitate queries of national, state and local databases; show on-duty units and current status; and display the current call for service queue. In some cases 911 integration, GIS mapping and past history at an address can be displayed.
  
  

Effects

• Use of a CAD system by a police department results in coordinated effort of call takers, dispatchers and officers. Coordination allows calls to be easily prioritized and emergency resources can be dispatched for maximum effect on the community. The public is impacted by decreased response time which leads to more crimes stopped while in progress and an increased arrest rate of offenders. CAD logs also function as evidence and because of the timeliness of the entries, can help convict an offender in a court of law.
  
  

Considerations

• While a police department CAD system assists the dispatcher in retaining and retrieving facts there is still room for human error. In the article "Are CAD Systems Becoming Too Complicated?" authors Mike Scott and Randall Larson caution us that complex systems can hamper the effectiveness of a CAD system. "No matter how intuitive the graphics, there is a limit to the amount of data that one person can process effectively."