In the United Kingdom and in the United States, public video systems have been used to prevent crimes and to monitor high-risk locations. Although privacy advocates promote various scenarios in which surveillance images might be misused to compromise the expected privacy of individuals, the value of video to law enforcement and the justice system is clear. Video is used to illustrate and support the testimony of witnesses and to act as a "silent" eyewitness. Visible closed-circuit television cameras deter crime in the surveyed area. Video use has its difficulties, however. These include damage to videotapes each time they are run through a VCR and an absence of detail in analog video images. Although digital video systems provide advantages in image quality and ease of use, compression when exporting images from surveillance systems can remove vital detail in the image. This can be remedied by collecting the hard drive from the digital surveillance system and applying tools used in computer forensics to extract the video; however, this technique can be costly. Another difficulty is poor camera placement in relation to lighting and distance from the people covered by the camera. Cooperation among law enforcement, businesses, and system providers can mitigate many of these problems. 7 figures and 7 references