Cameras or video surveillance can deter crime by creating the threat of being detected. Surveillance systems have two primary functions: to deter crime by device visibility and to capture evidence that will aid in prosecution of criminals. The price of a system should not always be the determining factor when making a system choice. Law enforcement is concerned with the output of the system in the form of usable video or still imaging. In most cases the placement of the cameras and the video format will be the most important factor in making the evidence usable to law enforcement.
Camera locations should be in well lighted areas or in places with good back-lighting. Try to place a camera near the main entry point at about eye level. The camera has the best chance to capture evidence if it is within 14 feet of the entry point. For surveillance used to cover larger areas, attempt to place the camera as close as possible to objects that have a potential for exploitation.
If the system uses VHS tape, replace the tapes frequently as they degrade quickly when re-used. Digital systems have many different formats for capturing data. Compression simply makes the data smaller so more data may be stored in the system. However, the greater the compression the greater the chance for data to be washed out when uncompressed by law enforcement personnel for forensic video analysis. In any event, compression is usually balanced by budget, and in the end, any surveillance is of some use and thus a good investment.
For questions regarding camera/video surveillance contact:
Forensic Imaging Supervisor
Phoenix Police Department