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Role of Global Positioning Systems (GPS) in policing

K. Jaishankar
K. Jaishankar
Mecosoft Systems Pvt. Ltd.

GPS technology can offer numerous benefits to Criminal Justice agencies of all types. For some agencies, the navigational capabilities offered by GPS might enhance efficiency and safety. These navigational applications can be used to support a variety of policing and criminal justice functions. Other agencies might be interested in using GPS to carry out special operations or to provide enhanced personnel safety. GPS is still an emerging tool in Indian policing, which may offer a multitude of unforeseen applications for law enforcement and the criminal justice system. We can expect to see this technology decline in cost and/ or improve in quality in the years to come. As a navigational tool, GPS can be a powerful asset for law enforcement users. This paper deals with the potential of GPS in policing.

The availability of Geographic Information System (GIS) and Global Positioning System (GPS) technologies to the modern law enforcement profession represents a quantum leap forward in operational management and strategic planning capabilities. With GPS/GIS, the modern law enforcement agency now has a new array of tools for combating crime and managing traffic. These new technological applications provide police officers with a wide variety of analytical capabilities and resource management information. GPS/ GIS will allow them to direct resources in a manner that is both flexible and responsive to the dynamic and volatile nature of public safety operations. GPS technology, when combined with automated wireless mobile field data gathering, represents the path that law enforcement agencies will be taking into the future for records and resource management. GPS data, embedded in the DBMS, will provide the common thread that binds the tapestry of modern lawenforcement business process. This technology will revolutionize the way in which the police department is conducting its business. The challenge will be to harness the power of GPS/GIS, and to point their development in a cost effective direction so that all law enforcement agencies, both large and small, can reap the benefits that these applications will afford. As a tool for law enforcement, GPS can assist agencies by increasing officer safety and efficiency.

What is GPS?
The United States Coast Guard defines GPS as “a satellite-based radio-navigation system.” In layperson terms, GPS operates when a network of satellites “read” the signal sent by a user’s unit (which emits a radio signal). A GPS unit receives data transmitted from satellites at least three satellite data inputs are necessary for accurate measurements.

The unit then interprets the data providing information on longitude, latitude, and altitude. GPS satellites also transmit time to the hundredth of a second as coordinated with the atomic clock. With these parameters of data and constant reception of GPS signals, the GPS unit can also provide information on velocity, bearing, direction, and track of movement.

GPS receivers can be integrated with other systems, such as a transponder or transmitter. The transmitter takes information from the GPS receiver and transmits it to a defined station, such as a police dispatcher. The dispatcher must have the system to both receive the transmission in “real time” along with the GPS data. To be truly useful, this information must be integrated with a Geographic Information System (GIS), which has a map of the community and translates the longitude and latitude into addresses.

GPS units allow users to process this information regardless of weather conditions and location anywhere in the world—Land, Sea or air. As a general rule, however, GPS receivers will only work outside where the signal from three satellites can be clearly received. Thus, transmissions from police cars inside a structure—such as a parking garage—will be obstructed. Similarly, use in a building will generally be limited.

GPS was originally developed by the military to aid in navigation. Naval vessels, aircraft, and land vehicles could all determine their exact location to a high degree of accuracy in a matter of seconds without human error. A civilian GPS system now allows commercial and private users to enjoy the ability to accurately navigate anywhere in the world. Currently, corporations are developing GPS as a way to enhance customer service, to track inventory, and enhance security.

GPS and Policing
GPS technology can offer numerous benefits to law enforcement agencies of all types. For some agencies, the navigational capabilities offered by GPS might enhance efficiency and safety. These navigational applications can be used to support a variety of policing and criminal justice functions. Other agencies might be interested in using GPS positioning technologies to carry out special operations or to provide enhanced personnel safety.

GPS is still an emerging tool, which may offer a multitude of unforeseen applications for law enforcement and the criminal justice system. We can expect to see this technology decline in cost and/or improve in quality in the years to come. As a navigational tool, GPS can be a powerful asset for law enforcement users. The Riverside (California) Police and Ventura County (California) Sheriff use GPS to enhance the efficiency of their aviation units. Using computerized maps of their jurisdictions in conjunction with GPS, aviation personnel can determine their exact location, their speed, and their estimated time of arrival when responding to calls. A GPS unit provides a computer with constant updates of the helicopter’s location. The computer is able to plot the location on a map of the agency’s jurisdiction. This map is displayed for the flight crew; this enables flight personnel to always know their true location.

Aviation personnel observing activities on the ground might not know the exact location of the events, which they are witnessing. Using a computerized map integrated with a GPS unit, these observers could accurately direct personnel on the ground to a specific location. Aviation personnel do not have to fumble with paper maps or provide vague locations in reference to major streets or landmarks (“Subject is three streets west of Main”).

This technology can improve the performance of aviation personnel and enhance communication between members of different units. In addition to aiding aviation units, GPS could easily be applied to assist personnel operating in ground vehicles. The advantages of GPS for ground-based personnel are most profound for employees working in large jurisdictions. State and county officers of United States were recently assigned to a particular jurisdiction will never be lost if their vehicle is equipped with a GPS unit (although there is still no substitute for a solid knowledge of one’s jurisdiction). Officers engaged in a pursuit, which has taken them outside of their jurisdiction, can always determine their precise location. Officers responding to a mutual aid call can plan their route and estimate their time of arrival. There are a variety of other GPS applications, which go beyond supporting patrol and aviation functions. Personnel who routinely travel in unfamiliar or semi-familiar territory may find GPS helpful in improving their efficiency.

For example, state-level investigators may frequently be called to assist in major crime investigations in an area encompassing hundreds or thousands of square kilometres. GPS systems could help guide these employees to the exact location where their assistance is needed. Correctional personnel might frequently be called to transport prisoners and detainees between locations. Having access to a GPS system provides an extra level of security.

The positioning capabilities offered by GPS may also contribute to the success of specialized law enforcement operations. A bait vehicle is one such example for the capability of GIS and GPS. A bait vehicle was equipped with a GPS unit, which relayed information about the vehicle’s location to a remote unit. This allows investigators to easily track the vehicle and make an arrest once it had been stolen.

The studies show that, one such program operated in Minneapolis led to a 60% reduction in auto theft after only one month. GPS may make it easier for investigators to track a vehicle’s movement over longer periods of time and across larger distances. A team of investigators might not simply want to track a vehicle to apprehend the thief. Using GPS, a vehicle could be tracked for several hours until it is taken to a “chop shop” in another city. This would enable investigators to attempt to prosecute a ring of car thieves, rather than just targeting isolated offenders.

In addition to being a tool for law enforcement “bait” operations, GPS can also provide enhanced security in the private sector. By outfitting expensive (and relatively mobile) equipment with GPS units, stolen items can be quickly located and recovered. Corporations owning these vulnerable “mobile investments” (semi-trailers, heavy machinery, construction equipment, automatic teller machines, etc.) could enjoy an element of security knowing that their inventory is safer. Law enforcement agencies might also profit by being able to clear major theft cases. In addition to tracking stolen cars, investigators could use GPS to create bait operations for a variety of vulnerable merchandise. An area having problems with the theft of heavy machinery could set up an operation to attempt to catch the guilty parties. This would allow investigators to target a wide variety of theft operations. In addition, GPS is increasingly being used as a precise method of defining locations of crimes, evidence, and traffic accidents.

The future prospects of GPS technology are virtually limitless. Police officers operating in unfamiliar territory will always know their location. Investigators can track stolen merchandise anywhere in the world (imagine if a credit card sized transmitter could be slipped into a stack of $100 given as ransom money). The greatest advantage of GPS technologies is their ability to help police officers do their jobs more efficiently and with a greater degree of safety. The accidental bombing of the (Chinese Embassy in Belgrade, Yugoslavia is a testimonial to the vital need to keep maps updated.) When mapping and positional systems are properly integrated, GPS can be a powerful asset to support law enforcement agencies in a broad (and expanding) variety of operations.

GPS Applications in Policing

Automatic Vehicle Location (AVL)
One of the most popular applications for GPS/GIS technology has been fleet/resource management through AVL. These systems provide efficiency of response and help ensure officer safety. AVL becomes AVLN (Navigation) by comparing GPS data against known road condition data. AVLN provides the officer with accurate information concerning the best response route to an incident. It also gives police officers and supervisors, information that allows the closest patrol officers to be dispatched to a particular incident.

Should an police officer need immediate assistance, AVLN is a safety net. It gives other officers or rescue personnel precise information about the location of an officer in need of assistance. This approach is also being applied to commercially available navigation systems so that motorists will no longer have to guess their location when requesting assistance from emergency response personnel.

Critical Incident Mapping, Management, and Documentation
Critical incidents require the coordination of numerous emergency response resources over large distances and substantial lengths of time. It is necessary to keep documentation that will assist with incident management, and which will provide a record for subsequent debriefing, training, and court purposes. Time-critical GIS applications for critical incident management represent an effective way to manage and document incidents, especially when coupled with real time (GPS) AVL data. Advanced Transportation Management Systems (ATMS) The Intelligent Transportation Systems concept relies heavily upon technology to support the efficient use of multi-modal transportation systems. Perhaps the most important of these transportation systems, from the perspective of the first responder, is the road system. Almost everything that the first responder does is tied to the road system in some way. Most people associate law enforcement with the prevention, reduction, and prosecution of criminal activity. In fact, a large portion of local law enforcement resources are involved in facilitating the movement of people and vehicles in a safe manner. It is this part of the law enforcement mission that ties it closely to transportation systems.

Advanced Transportation Management Systems (ATMS) are heavily dependant upon GPS/GIS technology to provide data about the road system. This information is translated into actions, by traffic managers, which help to control and expedite the flow of traffic. Law enforcement personnel use the same information, relayed to them by traffic managers, to clear roadway blockages. The same information, supplied to the average motorist, can help them decide a course of action that will keep them from having to wait in stalled traffic. This symbiotic relationship has the effect of making the safest, most efficient use of the road system.

Mobile Computing and Field Reporting Systems
Wireless mobile computing provides the front-end data collection capability that efficiently captures timely information for a variety of investigative and analytical purposes, not the least of which are GIS records management and analysis. Adding GPS data to the DBMS means that the GIS applications will run more efficiently, and with fewer spatial data translation errors.

Field reporting and data capture enables investigators to assemble case files containing information that was previously next to impossible to obtain and adequately correlate. With the use of differential GPS (DGPS), investigators can precisely relate evidence placement to crime scene reconstruction diagrams. The same applies to accident investigation and reconstruction. By tying evidentiary information into a GIS format, cases can be graphically displayed to show the temporal and spatial relationships of crime reports, witness statements, evidence, and crime scene drawings. GIS provides for a variety of presentation formats. These presentation formats can be easily and automatically displayed for court, training, and briefing purposes.

Field captures of traffic citation and accident data supplies law enforcement managers with valuable information to be used for selective enforcement and resource management purposes. For traffic managers and engineers, this type of data provides information for traffic engineering or flow management needs. Once again, a GPS component added to the data record, gives the users valuable information about the exact location of particular problems when used with the appropriate GIS application. This crime and traffic data can be analyzed and accessed by field units and investigators through the use of mobile computing. Automated field reporting data is stored and collated in crime databases. This data is, in turn, made available for a number of investigative, informational, and analytical purposes. The advent of GIS makes this information come alive in easy to comprehend presentation formats. GPS data, tagged onto the DBMS, supplies the key to effectively supporting the capabilities of GIS.

Monitoring probationers and parolees by GPS
Since probationers have tended to change addresses frequently, the mapping system’s address verification function has helped probation officers maintain contact with their clients. A map displaying probationer addresses with overlays showing the locations of potential risk areas (e.g., schools, high-crime areas) and service providers (e.g., employment training and drug treatment facilities) also has been helpful. Finally, supervisors have used the mapping package to manage probation officers’ workloads by producing maps showing the locations of each probation officer’s clients, color-coded by the required level of supervision (i.e., minimum, regular, or intensive)

Continuous monitoring of the location of the probationers can be done through a Global Positioning System. The cost of the receivers, although decreasing, is certainly a factor. Electronic ankle bracelets can been used to monitor probationers; typically, these devices will trigger a telephone call to the probation officer when the probationer moves more than a specified distance from a location. Such devices could, in theory, also be used to detect violations of restraining orders or other special conditions of probation or parole (e.g., a person must keep a certain distance away from schools or child care facilities)

Florida-based Pro Tech Monitoring ( has developed a GPS-based tracking system, called the SMART System, that combines Trimble’s miniature Lassen-SK8 GPS board and cellular technology into a unit worn by the criminal offender. In addition to the 3.5-ounce, tamper-proof ankle bracelet, the system includes a portable tracking device (PTD) that is electronically leashed to the ankle unit. The PTD contains the GPS receiver and cellular communications.

Unlike conventional house arrest systems that only monitor when offenders leave or return home, Pro Tech Monitoring’s SMART system keeps track of offenders anywhere, at all times. The unit is ‘smart:’ it contains “rules of release” which stipulate where the offender should be at all times. If an offender breaks these rules of release, the system automatically warns the offender and then sends a message to a control center if the problem is not immediately corrected. Police departments in at least 16 states of United States use SMART (Satellite Monitoring and Remote Tracking).

The SMART system is appealing because it uses existing technology, transforming the traditional electronic ankle bracelet from a monitoring device to a tracking device. It records where a wearer of the bracelet goes and enables officers to monitor the person’s movement via PC-based workstations and Internet-accessible maps.

Here’s how SMART works
  • Portable tracking device: For GPS to work, an offender must carry a GPS receiver, complete with a microprocessor and antennae, to record locations. The offender carries the device in a waist pack. The recorded data is fed to a data center or a monitoring station via a cellular transmission when portable or via a phone line when the device is charging at the offender’s home. The microprocessor in the unit can be programmed to create inclusion zones (places the offender must be at certain times) and exclusion zones (places where the offender is not allowed). If either zone is violated, the receiver sends an alarm via pager to the monitoring station and the victim
  • Electronic ankle bracelet: Equipped with a radio transmitter, this traditional monitoring device works in tandem with the GPS receiver, essentially acting as an electronic tether. The receiver constantly measures the signal strength in the ankle bracelet. Thus, if the receiver is left behind in the house while the offender goes to work, the receiver will set off an alarm at the monitoring station. Both pieces of equipment also have tamper-detection features to keep offenders from trying to remove or dismantle them.
  • Monitoring stations: The data collection center of the operation requires only a PC workstation and Microsoft Corp. Windows-based software designed by Pro Tech. When SMART is in action, the screen shows maps ranging from single streets to citywide zooms. “Blips” indicate where the offender is. Staff members keep pagers and cell phones that take violation calls from the GPS receiver.
  • SMART surveillance system: Through a secure Internet connection, a monitoring station can access and save information to a Pro Tech-created database of national maps, longitudinal and latitudinal points, maps of offenders’ movements and customized reports.
GPS and Police patrolling
From a management and safety viewpoint, Police managers have long wanted to be able to locate any patrol unit on a map at any point in time (where are the units right now?). Now police patrolling personnel are able to use GPS sensors for that utilize from three to seven satellites for precision; three receivers will sense position to a hundred yards or so; seven receivers will be accurate to within a few meters. These receivers also have a small computer chip built in so that they can do the required timing and calculations internally and report position in either longitude/latitude or UTM (Universal Transverse Mercator) form with pre-determined regularity. That can in turn be fed into either a PC, or into a radio modem for transmission back to base. Typically, each unit would report position every minute or so.

At the base station, usually the control room, these position reports would be received and used to display the current location of each unit on a large computerized map (usually on a BIG screen or projection); it has to be large to display the entire area in enough detail to be useful. If an accurate map is available, this is relatively easy to do. GPS can be useful in the urban policing setting primarily as an officer safety device. In the urban setting, the officer is most often on his way to or at a call, and the control room knows where that is; and in between, the patrol officer can periodically indicate location, so GPS is not of substantive value for dispatching in urban areas. It can be very helpful, however, if the officer is hurt, or taken, since other cars can be quickly vectored on the location of the subject patrol unit. However, GPS is most useful in the rural/ highway patrol situation where units spend most of their time seeing and being seen rather than responding, and where assistance can be far away. Similarly, given long distances involved in rural areas, knowing exactly where all available patrol units physically are can allow the dispatcher to send the unit that will arrive on the scene the fastest, so GPS can be of real dispatching assistance in the rural or highway patrol setting.

Some Words of Caution About GPS in Policing
In exploring the variety of GPS options available to law enforcement agencies, it is important to consider the degree of precision offered by each system. Many larger electronic stories sell a basic, handheld GPS locator unit for a few thousand rupees. These units will simply give the user readout of their location with a varying degree of accuracy (most civilian units are accurate to less than one hundred meters). More precise units, and systems which pinpoint location on maps, will be more expensive in that they require “differential correction equipment”. Such units, however, can identify a location within one meter.

Interestingly, the reason for the lack of precision in commercial GPS is not a matter of technology, but one of policy. With the DOD stopping its intentional distortion, all GPS receivers will be able to pinpoint positions on the earth within one centimeter. Police Departments integrating GPS and computerized maps need to be sure that the accuracy of the maps matches the precision of their GPS units. Although the quality of both GPS and computerized maps is improving, care must be exercised to ensure that the maps will reflect the actual position of the GPS unit. Maps must also be regularly updated to reflect significant changes within a community.

GPS in Policing: The Indian Scenario
In India, Bangalore police, Hyderabad police, Mumbai police, Goa police, Kerala police, Delhi police and Chennai Police are the front-runners in using GIS and GPS for Crime prevention and control. But the application of GPS in policing has not taken pace as done in developed countries. In this context, there is a need to study the current problems that hamper the development and availability of GPS in Police Departments.

Hardware and software costs
The cost of hardware and GIS software starts at a few thousand Rupees. Still, the cost of minimum configuration—a PC, monitor, printer, and desktop mapping software, GPS can be prohibitive to police departments that must continuously weigh the costs and benefits of GPS against other crime prevention activities.

GPS will be more complicated and harder to learn for police personnel, so, special training courses are often required to use GPS effectively. This requirement is also a serious obstacle for Indian police departments. Indian police departments usually depend on one or two persons who are familiar with GPS/mapping; when these persons leave or, transferred to another area, the department also loses its GPS/mapping capability. One approach to overcoming this obstacle is to develop a separate crime-mapping department. In this department a new breed of people for the Indian criminal justices system called crime analysts should be recruited. This department should be fully dedicated to work only on GIS/GPS applications. Apart from this, various levels of police personnel should be trained by crime mapping department.

The GPS application in Indian Policing is in its infancy. Large-volume commercial applications such as cellular phones, personal communication systems, and in-vehicle navigation systems will fuel continued development of these technologies. What was ultimately the domain of the Department of Defense is rapidly becoming available for business, private, and general government use. Policing and public safety in general, will benefit from these market forces. It is clear that there are number of GPS applications for policing.

The challenge for the next decade will be to create hardware that is small, rugged, and within the budget of the average police department. Along with this goes the challenge of creating inexpensive applications that are integrated, flexible, and which can be supported by limited staff maintenance and training resources. As with many other technologies, the GPS/GIS industry must meet these requirements if it is to be successfully introduced into the Police Departments.

At this juncture, it is essential for the development of a nodal agency to implement and manage GIS/GPS in Indian police departments. Hence, it is proposed that, a National Crime Mapping Research Center (NCMRC) should be created under the Ministry of Home Affairs in the Capital and all the states should have a State Crime Mapping Research Center (SCMRC) and it should be connected through a network with the NCMRC. Apart from this, GIS/GPS technology should be added to the curriculum for the Police training at the Sardar Vallabh bhai Patel National Police Academy, National Institute of Criminology and Forensic Science, Central Detective Training Schools and State Police Training Colleges. It would enable the police personnel to use the GIS/GPS in an efficient manner, to play an effective role in crime prevention and investigation.

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