As seen in Police Chief Magazine, June 2002
By Philip Broadfoot, Chief of Police, Waynesboro, Virginia; and Thomas P. Dugan, Law Enforcement Consultant, ITT Industries, Roanoke, Virginia
When it comes to public safety and disaster preparation equipment, most managers think of advanced weaponry, vehicles, and communication devices. We often lack the funding for, or do not make a priority, the essential stealth equipment necessary for protecting our officers and communities in low-light settings.
For years, most police departments, when operating in darkness, have relied on spotlights and any method to improve on them-door-post spotlights, roof-mounted remote-controlled spotlights, handheld spotlights, and various grades of flashlights and lightbar-mounted spotlights, to name a few. After years of relying on spotlights and flashlights, the Waynesboro, Virginia, Police Department needed a safer, more effective method to operate tactically in the dark.
In response, the department secured both night vision and thermal imaging equipment. Night vision aided in identification of criminal activity and suspects in dark situations, and thermal imaging helped officers detect criminal activity and perform search and rescue functions. However, before the department realized the benefits of imaging technologies, it had to overcome issues involving cost, training, and the lawful use of the equipment in the field.
How Imaging Technologies Work
Imaging technologies can prepare law enforcement for situations ranging from disaster preparedness and responsiveness to high-risk warrant service, jail perimeter security, search and rescue, surveillance, evidence gathering, foot pursuit, SWAT/tactical maneuvers, weapon firing, and K-9 activities . However, both image intensification and thermal imaging technologies have distinct advantages and disadvantages to law enforcement users.
Image Intensification
Image intensification is the technology most often referred to as night vision . Image intensification devices can be monoculars, binoculars, weapon-mounted, camera-mounted, or head-mounted for specific law enforcement needs. Such devices contain a tube that collects the available light and intensifies it thousands of times. Image intensified night vision is designed to operate in extremely low light conditions from 0.1 lux (full moon) to 0.0001 lux (moonless overcast).
In second- and third-generation image intensification systems, an objective lens collects light that can’'t be seen with the naked eye and focuses it on the image intensifier. Inside the image intensifier a photocathode absorbs the light energy and converts it into electrons. These electrons are drawn toward a phosphor screen after passing through a microchannel plate that multiplies them thousands of times.
When this high, intensified electron image strikes the phosphor screen, it causes the screen to emit light that you can see. Since the phosphor screen emits this light in exactly the same pattern and degrees of intensity as the light that is collected by the objective lens, the bright nighttime image you see in the eyepiece corresponds to the outside scene you are viewing.
Image intensification allows officers and security personnel to see, film, and identify a perpetrator in extremely low light. It can be used to collect evidence to convict in court because it can achieve facial recognition and pick up critical details, such as shirt patterns and handheld objects, without distorting the image.
Thermal Imaging
Thermal imaging technology senses thermal radiation in the 7.5 to 13 .5 micron range, which creates a thermal picture by measuring very small temperature differences that can’'t be seen by the human eye. A thermal unit uses thousands of electronic detectors to display an image on a video monitor, creating an image of emitted heat energy.
Thermal imaging is beneficial in conditions involving fire, fog, snore; or water or in evhich a perpetrator is hiding (such as behind bushes). The technology is best for detecting rather than identifying people. You can see shapes and may even be able to determine that the subject is human-but identification is impossible in most cases.
Waynesboro’'s Safety and Funding Issues
The Waynesboro Police Departments 50 full-time and 31 reserve officers serve an industrial, independent city with a population of 20,000 . While violent crimes in 1Vavnesbcrro are below state and national averages, larceny and drug violations are significantly higher.
Wavnesboro’'s ability to collect evidence, find prowlers, conduct stakeouts, and stealthily approach the scenes of suspected cringes in progress was hampered by a lack of night vision or thermal imaging equipment. Without the technology, officers compensated by moving quickly- with regular spotlights in the hope that they . could achieve with speed and light what they could not do .stealthily. These tactics did not offer officers an advantage over the criminals and greatly increased the danger to officers and citizens.
Police officers face a greater risk of injury, or death at night because of higher crime rates during these hours. Even with a heightened threat, most departments do not have night vision or thermal imagers. Why?
Cost is a significant limitation. Top-quality image intensification devices cost between $1,900 and $3,5011, while top-quality thermal imagers cost more than $70,000. Many_ current grants provide for night vision and thermal imaging technology. The Office of National Drug Control Policy (ONDCP) includes both night vision and thermal imaging technologies on the list of 30 items departments can apply for through the Counterdrug Technology Assessment Center’'s (CTAC) grants . In fact, the two imaging technologies are the most requested items.
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The monocular uses a military style image intensifier tube in a high-performance housing designed for multiple uses. This unit can be handheld, head-mounted, weapon-mounted, or adapted to a camera or camcorder.
Call 800-448-8678 for more information or visit our website: www.nightvision.com.
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For the Wavnesboro Police Department, securing adequate funding Was the greatest obstacle to obtaining the technology. We learned quickly that you get What you pay- for. In attempting to save, the department purchased a lower quality, second-generation model that turned out to be fragile, difficult to deploy; and rarely used. The department also borrowed top-quality night vision for planned operations from other departments, but coordination was problematic. Third, the department practiced with our local fire department’'s thermal imaging device, but concluded it was unsafe and cumbersome in a police environment. Ultimately, the department was able to secure third-generation night vision equipment using drug seizure money. Later, a thermal imaging device was procured under the U.S . Army transfer grant program.
Integration, Training, and Implementation
Only minimal training was needed to use the image intensification (night vision) equipment. The units are compact, virtually” indestructible, and easy to focus. The agency was able to simply email information about the units to members of the entire department, distribute the three devices in plastic boxes, and encourage their use. Integration of the technology in the patrol environment was flawless . Use of the devices increased as officers began using them during building searches and for the purpose of locating prowlers, teenage drinking parties, and trespassers in the parks.
The department found that the units were so small that they easily could be overlooked and lost under file seat in a patrol car. Some personnel expressed concern that it would be difficult for officers to climb in and out of their patrol cars carrying these devices and additional gear without dropping them. In response, the department placed the devices in plastic boxes that were easy to carry and protected file equipment. The boxes are left in the department in a cabinet and any officer can take one out at any time to use on patrol or for special operations.
The single thermal imaging device came in its own hardened case, so it was immediately deployable . Officers initially assumed that the thermal imaging device would be as easy- to operate as the night vision equipment. When the department’'s thermal imaging training officer left for another agency, these officers struggled with learning how the equipment worked. The thermal imaging device required several more steps and switches to operate than the night vision device. When officers encountered difficulties at any step, they immediately turned away from it.
The Wavnesboro Police Department assigned a single officer to take over file care, handling, and training of the device. That officer joined a thermal imaging users group to learn more about the issues and uses of the technology nationwide. Training was the key to making the device practical for use in the patrol unit. The only way to learn was by using the device in the field. Another barrier the department identified %vas that the device used video camera batteries, which have a very limited operational time after several recharges. The unit needs to warm up before it will turn on, so many officers thought that it was broken because they did not wait for the device to warm up.
After several months, the department got past the obstacles and found that the devices worked extraordinarily well. The device is gaining popularity, although not as much as the night vision equipment because it is bulkier and slightly more complex and has a steeper learning curve. Nevertheless, the unit fills critical gaps in patrol, investigative, and tactical operations in limited light environments.
Before deploying the thermal imaging device, it is very important that officers receive specific instruction on how to use it legally. This should include study of the United States Supreme Court’'s decision in Kyllo v. United Staid (June 11, 2001), which held that thermal imaging surveillance of a private home constituted a search under the Fourth Amendment and was presumptively unreasonable without a warrant.
Ultimate Findings
A number of valuable lessons have been learned through the acquisition, training, deployment, and maintenance of imaging technologies in the department. It is critical that officers buy into file value of a new tool, understand its practical and legal operation, and maintain it so that it will perform as designed . The Waynesboro Police Department found the advantages of the equipment to be well worth the work required to overcome the barriers to implementation.
While technology is useless without a trained officer operating it, the imaging devices acquired and used by the department have had a positive impact on the organization. The ability to see in the dark has greatly enhanced the level of specialized protection the agency can offer to its citizens.
Law enforcement executives should consider this technology as a tool that can be employed by agencies of any size to enhance their operations . Taking advantage of file unique funding opportunities that are available can help to mitigate the financial impact of the acquisition.
Looking Ahead
Today, manufacturers of image intensification and thermal imaging technologies are in the process of developing and producing night vision sensor fusion technology. Fusion combines the respective strengths of thermal and image intensification technologies, while mitigating their limitations. The sensor fusion technology maybe available to law enforcement in two to three years and will likely cost close to $10,000 per unit .
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Side bar: 3D Imaging Aids Gang Task Force
In Westerfield, Connecticut, detectives assigned to assist a federal gang task force that was investigating illegal drug transactions being conducted by a street gang found that night vision equipment greatly aided their surveillance abilities at night.
Gang members sold narcotics openly in and around housing projects, believing they were secure due to the location and the cover of darkness. The task force observed the gang from the third floor of an elementary school, approximately 1,000 feet from the target area, using file night vision devices. “We recorded hours of videotape, and the video was so clear that all participants were recognizable to file point of positive identification,” said Detective Lieutenant James Cetran.
On one of the videotapes, one of the gang members could be seen walking over to a number of his friends and lifting his shirt. A semiautomatic handgun was clearly visible protruding from his waistband . The suspect pulled file gun out and showed it to his friends. Eight members of the Los Solidos street gang were arrested on federal warrants and prosecuted. All eight were convicted in court. Much of the credit went to the videotaped evidence.
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Courtesy of ITT Night Vision and Police Chief Magazine
Call 800-448-8678 for more information for more information on night vision or visit ITT’'s website: www.nightvision.com.