Law violators have fled from authorities for as long as the police have been chasing them. Stories of bank robbers riding horses out of town followed by the sheriff's posse fill the folklore of the Old West. The Keystone Cops once provided comic relief in cinema as they depicted officers chasing-but never catching-hoodlums and scoundrels.

As cars replaced horses and trains as the preferred means of escape, the Prohibition Era brought reality and folklore together. Not only did the police pursue violators suspected of transporting illegal caches of alcohol (the bootleggers), other "crimes of flight" such as auto theft and joyriding were added to this high-stakes game of "cat and mouse."

Today, with the immediacy of worldwide coverage through streaming video and airborne news cameras, Hollywood and the media have found a niche market in the coverage of endless police pursuits as well as creating fictional ones in film. This glamorization of "the chase," however, is at odds with policing efforts to limit the number of pursuits and end them without loss of life or property. Now, emerging technologies may offer a solution once thought impossible: to stop a fleeing violator quickly, yet safely. The news may be more boring without a pursuit to break the tedium, but the police and the citizenry will breathe easier knowing their communities are safer.

Limiting the number of pursuits and ending them without loss of life or property, sadly, is a continuing challenge for law enforcement. In fact, the number of deaths each year following a police pursuit typically exceeds that due to any other police activity.

The National Highway Traffic Safety Administration (NHTSA) recorded a total of 2,654 fatal crashes involving 3,965 vehicles between 1994 and 2002 as a result of police pursuits in the United States. Unfortunately, 3,146 persons lost their lives in these incidents.

Of the total number of fatalities, 1,088 deaths were of persons not in the fleeing vehicle (the vast majority of which were not involved in the pursuit in any way prior to their death). 102 of the fatalities were pedestrians or bicyclists, 40 were police officers, and 946 were occupants of vehicles uninvolved in the police pursuit.

Additional research with agencies in Florida, Nebraska, and South Carolina revealed that in more than 1,200 police pursuits, property damage occurred 20 to 40 percent of the time, and injuries from crashes resulted 12 to 41 percent of the time.

The Pursuit Management Task Force

The National Institute of Justice's Office of Science and Technology, in conjunction with the National Law Enforcement and Corrections Technology Center, formed the Pursuit Management Task Force (PMTF) in August of 1996 to consider these types of issues related to police pursuits. More than 400 police agencies nationally participated in a PMTF survey.

A central theme of the survey was the potential of "vehicle stopping" technologies to aid in the termination of a police pursuit. The PMTF concluded that any vehicle stopping technology must not only pass the Fourth Amendment test for reasonableness, but also must fit within general legal mandates for the appropriate use of force by the police.

PMTF members also concluded no singular technological solution had yet appeared to address the issue of how to stop a vehicle during a pursuit, and that government and researchers had not yet found "the way" to stop a fleeing car.

As a component of its research, the PMTF contacted Dr. Edward Scannell, the U.S. Army's Research Laboratory Specialist, to provide technical expertise regarding vehicle stopping technologies. Dr. Scannell and PMTF members identified three vehicle stopping methodologies considered to be capable of stopping police pursuits: mechanical, chemical, and electrical.

Mechanical stopping devices (tire deflation, wire or metal barriers) are found most commonly in the form of spike strips. While spike strips were one of the few current technologies shown to be successful in stopping vehicles being pursued, this device has an inherent weakness. During a high speed pursuit, an officer(s) would be required to deploy this device ahead of the violator, thus creating undue risk to the officer and to the offender, as well as to any civilian vehicle in or around the area.

Chemical systems (gaseous, liquid, or solid such as powder) were another method to stop fleeing vehicles. According to the PMTF, a chemical would be introduced through a delivery system such as shooting a gas-filled projectile that explodes over or on top of the fleeing vehicle that would alter the fuel-to-air ratio and, in effect, disable the combustion process. One danger for law enforcement with this technology would be the exposure to potentially hazardous materials; however, the main limitation for this technology was the impracticality of an effective delivery system during the actual vehicle chase.

Electrical systems were the third category reviewed by the PMTF. While this technology was not fully developed at the time of the PMTF report, researchers projected the use of a preinstalled computer with a shut-off switch that could be used to "kill" the engine upon command initiation.

PMTF members also noted that some type of frequency emitting technology (microwave or electromagnetic pulse) could be developed to emit waves that would "short circuit" the vehicle being pursued, forcing it to stop. Using high-tech intervention offers the promise of capturing suspects safely in a way less damaging to vehicles or other property. These means offer the best solutions for the police to consider as they seek to mitigate the litany of problems caused by pursuits.

Future Potential

Since the time of the PMTF report in 1998, a number of significant advances in the private sector have been developed that may have future potential for law enforcement. Notably, almost as quickly as one technology is developed, a similar yet more advanced version seemingly appears on the horizon. To be effective, a pursuit termination technology must provide utility and transportability for use by the officer on the street. This would include the officer's ability and willingness to apply that technology in real-world settings.

While it may always be possible to compromise the effectiveness of any technology, the utility of pursuit termination technology should also include the political and social debate regarding how these tools should be applied and what would really happen if that chosen technology proves to be inefficient or ineffective.

Radio Frequency Modulation (RFM)

Perhaps the most widely known technology using a type of radio frequency modulation is General Motors' OnStar service, marketed worldwide as a means to aid motorists in need and track stolen vehicles. OnStar technology can remotely unlock a vehicle as well as immobilize it in the event of theft.

GM has added other services to include hands-free calling and automatic collision notification. GM hopes to improve its market share where stolen vehicle tracking is in high demand. In a similar way, this technology may have future utility for law enforcement as a pursuit stopping and anti-theft technology.

Matco Industries has also developed an on-board diagnostic system with remote capabilities. Using wireless technology, Matco has been able to integrate wireless networks in combination with the Internet to allow remote tracking of vehicle movements and speed as easily as accessing an Internet mapping program.

This technology was developed for the trucking industry to provide, among other services, speed threshold setting, automated collision notification, vehicle engine diagnostics, and anti-tampering detection. Interestingly, Matco claims that it can use encrypted data transmissions to locate and disable any vehicle equipped with this device.

The limitation of this technology is that it only works when a vehicle is equipped with the appropriate "hardware." This notion raises political and economic dilemmas. Would this technology be mandated for all vehicles, much in the same way that seat belts are now mandated? Would the oversight and control for this technology rest with private industry, or would government be required to manage and operate this system? What would be the cost?

And, while the PMTF panel recommended appropriate action be taken in the development of new technology, it stopped short of suggesting that all vehicles be equipped with an on-board disabling technology.

Texas Instruments is yet another innovator in the area of RFM, combining two technological approaches (immobilizer technology and remote keyless entry) in its Radio Frequency Identification (RFID) System. Texas Instruments intended RFID to help curb auto theft.

If a vehicle is equipped with Remote Keyless Entry (RKE) in addition to an immobilizer, the RKE controller can produce a new Ultra High Frequency (UHF) or "rolling code" each time the push button is used. This gains access to the vehicle. The transponder then encrypts the request from the reader based on a security algorithm, resulting in an encrypted message that is transmitted to the engine for evaluation.

If the encryption code is properly received, the vehicle will start. If the encryption code is not properly received, the vehicle will not start. Texas Instruments claims this technology is the first of its kind.

One inherent challenge with every technology is that someone will undoubtedly attempt to defeat it. This was true of the RFID technology developed by Texas Instruments.

A research team at John Hopkins University discovered a way to defeat the immobilizer security system by cracking the code and, in essence, stealing its own cars. Fortunately, researchers also developed a better encryption device to make this transponder more secure.

Targeted Impulse

Targeted impulse (TI) systems are another category of remote stopping technologies that are also challenging fundamental assumptions. This technology was first observed in the defense industry during the early testing of nuclear weapons as an electromagnetic pulse (EMP) effect.

The effect was a production of very short but intense electromagnetic shock waves. This pulse of energy produced a powerful electromagnetic field sufficient to produce a strong burst of volts on exposed conductors. The military significance was the potential damage to computers, radio systems, and radar receivers, where TI ordnance could literally shut down an enemy's computer systems. The problem with this form of TI is that all computer equipment in the path of the impulse would be particularly vulnerable to electromagnetic effects.

Since the military's delivery system is not suitable for police use, another means must be found to disable a pursued vehicle while not also impacting the other automated systems in the path of the EMP.

Dr. David Giri, former physics professor at the University of California Berkeley, founded the company ProTech to address civilian applications of radio wave technologies for police use. He has been working with law enforcement to develop a radio wave stopping system that could deliver a blast powerful enough to knock out vital engine electronics, making the targeted vehicle stall and slowly come to a stop.

The battery and capacitors to store the electrical charge are designed to fit into the trunk of a car. The officer would just need to "flick a switch" on the dashboard to send a burst of electricity into the antenna mounted on the vehicle. The antenna would produce a narrow beam of intense radio waves aimed at the vehicle being pursued, causing a surge of electricity in that vehicle, upsetting the engine firing signals, forcing it to stop.

One problem with this technology, however, has been the specific modality to be used by law enforcement. While law enforcement officials have reviewed this particular device, the delivery platform is still too bulky and large to fit effectively inside or onto a police car.

More importantly, the potential for collateral damage ("zapping" someone else's vehicle beyond the intended target) is an unresolved issue impacting its possible use. Additional research and development will be necessary before this product can become available as an effective pursuit intervention technique.

A prototype variation of the targeted impulse system is the StarChase system currently being tested by the Los Angeles Police Department. The pursuing officer would literally fire a GPS "tag" from a compressed-air launcher at the vehicle being pursued. This tag would stick to the vehicle and transmit the vehicle location to pursuing units. Officers would then follow (but not pursue) the vehicle to a coordinated location, in hopes of alleviating the need for high-speed pursuits.

Cutting to the Chase

While the emergence of RFM and TI technologies hold promise, they must be tailored for specific application by law enforcement. Unfortunately, with any new technology, there is no track record upon which to depend because the technology itself has not yet been fully developed. Other issues such as privacy and functionality also pose concerns.

While the public may readily support safety initiatives such as mandatory vehicle air bags, concern is often voiced when allowing the police greater authority to stop and detain an individual. For example, existing GPS systems offer tracking hardware for police to install onto a vehicle to follow in surveillance. If the officers hardwire this technology to the vehicle battery, they need to get a search warrant. If they instead covertly attach this technology temporarily to the underside of a vehicle using an independent battery source, they do not need a search warrant.

New technology requires an organization to move from the traditional to the innovative. Law enforcement should be willing to look to the future without the blinders of the past. In our voyeuristic society, we anxiously crowd around the television to watch when the news helicopters film the police pursuit of yet another criminal.

To elude arrest, violators often travel over 100 mph in 3,500-pound cars through red lights, against opposing traffic, and through the residential neighborhoods where our children play. As the chase entertains us from the safety of our living rooms and the news station's ratings spike, every car the criminal recklessly speeds by is put in very real and severe danger.

Some pursuits last a few minutes and others last a few hours. Some end with the violator giving up; others end in violent confrontations or suicide; and some end when the violator's high-speed vehicle crashes into an innocent family, ending their lives.

If the intervention technology detailed in this article could eliminate or mitigate a portion of high-speed pursuits, then its employment would be well worth the cost. Consider the devastating impact of more than 100 innocent people who are killed each year by criminals in cars that otherwise may have been safely stopped through the application of technology.

Lt. Gary Montecuollo is a 26-year veteran of law enforcement. He has worked as a detective, sergeant, and commander, and is currently assigned to the Special Investigations Bureau of the Glendale (Calif.) Police Department.