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Detecting Concealed Weapons: Directions for the Future

NCJ Number
Date Published
October 2007
3 pages
Publication Series
This article identifies the limitations of current weapons-detection systems (WDS), the status of research on WDS being funded by the National Institute of Justice (NIJ), and protocols associated with new WDS technologies.
Current WDS technologies do not provide a secure distance between the detection device, security personnel monitoring the device, and innocent persons in the vicinity of the device. This means that even though a gun or bomb might be detected on a person passing through the device, it could still be used or detonated at the point of the detection to kill people close to the WDS. Although this threat can be addressed by providing more secure space for a remote WDS, such space is not always available, and effective designs of a secure space for remote WDS are not feasible for high-traffic entrances. In the late 1990s, NIJ launched a program for detecting concealed weapons from a safe distance. Research found that passive millimeter wave (MMW) cameras offered the greatest potential. A passive MMW camera develops images from ambient MMW radiation, which, like infrared radiation, is invisible to the human eye. MMW, however, is more effective than infrared radiation in penetrating clothing to develop images of hidden objects. MMW cameras could detect concealed weapons at a remote distance without the carrier knowing that detection had occurred. This would give security personnel the element of surprise in detaining the suspect before he/she could use the weapon or reach the targeted area. Much work remains to be done, however, in improving resolution and range while reducing weight and cost of MMW cameras. Protocol challenges involve the management of privacy issues and the deployment and level of force to be used in detaining a person suspected of having particular types of concealed weapons. 3 notes

Date Published: October 1, 2007