California began installing the first electric perimeter fences around its prisons in 1992; six other States are planning to install them. The fences are lethal to anyone who comes into contact with them. Another new technology can detect the heartbeat of a person hidden in a vehicle and can be used to detect inmates trying to escape by hiding in a trash or laundry container being taken from a correctional facility. A system has also been developed to monitor offenders on home detention by satellite. This system uses cellular technology combined with the Federal Government's global positioning system for satellites. Smart cards are plastic cards embedded with computer chips that can store information about an inmate's movements, medical care, commissary purchases, treatment needs, meals eaten, and other topics. This technology has the potential for reducing paperwork. A technology called ground penetration radar can detect buried contraband or a tunnel being built under a prison. Other technologies being developed include body scanners to detect concealed weapons and contraband, noninvasive drug testing using eye scans and patches placed on the skin, a smart gun that can be fired only by the registered user, a language translator, and walk-through metal detectors that pinpoint exactly where the metal is. Illustration