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Practical Vehicle Equipment

By Richard J. Ashton, Chief of Police (Retired), Frederick, Maryland, and Grant/Technical Management Manager, International Association of Chiefs of Police, Alexandria, Virginia

Highway Patrol Vehicle

n 1909 Chief J. H. Haager of Louisville, Kentucky, predicted that the automobile would revolutionize police work and have a profound impact on policing.1 The police were not the only ones making use of the automobile, however; the American public also was becoming increasingly more mobile, as evidenced by the increase in car registrations between 1900 and 1930 from 8,000 to almost 27 million.2 Haager's prediction became true and the automobile is now a major factor in everyone's life.

The IACP Highway Safety Committee, working with police agencies, seeks ways to improve the working environment of police officers. The committee established in 2003 the Law Enforcement Stops and Safety Subcommittee (LESSS). During the 2005 Annual IACP Conference in Miami Beach, Florida, the subcommittee distributed two posters and a video, Your Vest Won't Stop This Bullet, intended for departments' use in training to mitigate the perils of traffic stops and other roadside contacts; the subcommittee's efforts continue. A wealth of information is available from the Highway Safety Committee through the IACP Web site at ( and the LESSS Web site at (

The performance requirements of police vehicles differ from those of consumer vehicless. Police officers are in their vehicles 10 times more than other drivers, are 1,000 times more likely to be parked at the side of the highway than civilian drivers, and are four times more likely to be involved in a crash than ordinary citizens.3 Moreover, a police vehicle is used in circumstances where high-energy crashes are likely to occur.

Production Protocols
improvements in police vehicles are, in part, dependent on the production protocols of auto manufacturers and aftermarket equipment vendors. The Ford Crown Victoria Police Interceptor has approximately 85 percent of the U.S. police vehicle market.4 Although the market for police vehicles appears large, fewer than 100,000 units are sold each year, an amount well below auto manufacturers' typical product lines of 200,000 to 250,000 units per year.5 Law enforcement does, however, provide a regular, stable source of income for manufacturers even if it constitutes but a small fraction of the market.

Base platforms for police vehicles are similar to those of consumer models, but manufacturers modify police vehicles to increase acceleration, top speed, drivetrain durability, brake capacity, longevity, and charging system output. They also add equipment, such as heavy-duty suspensions and stabilizer bars. But no uniform definition exists for vehicles sold with police packages. Each company determines its own design features, thus making it difficult to effect industry-wide changes. Departments need to consult with vehicle manufacturers when changing those items of equipment around which a police vehicle was engineered, such as tires, for any such change could compromise the operational safety of the vehicle.

Beyond initial police vehicle specifications, there are few guidelines available to either equipment manufacturers or installers of aftermarket equipment. Improperly designed and mounted equipment can become projectiles in crash situations and increase the risk of injury to vehicle occupants. Safety equipment, such as occupant restraints and air bags, can malfunction or deploy improperly due to substandard equipment installations.

Aftermarket Equipment
A great deal of thought goes into the safety design of today's vehicles; however, much of this work can quickly be negated by the improper installation or placement of aftermarket equipment in the police vehicle. Items improperly mounted or left unsecured in the interior of the police vehicle can present serious hazards to the vehicle's occupants in the event of a crash or rollover. These items include dashboard-mounted radar sets, laptop computers, equipment consoles, loose items on the rear package shelf or the back seat, shotguns in shotgun locks, in-car video cameras, and other protruding items. Items mounted on the dashboard improperly can be struck by a deploying air bag, in the event of a crash, and can become dislodged, striking and injuring the vehicle's occupants. The Florida Highway Patrol currently requires that all aftermarket installations in the passenger compartment of its vehicles withstand 30gs to prevent secondary impacts to its troopers during collisions. Every radar manufacturer offers a bracket that meets this standard.

When purchasing aftermarket police equipment, ask the manufacturer or the distributor to describe how the equipment was tested and what installation recommendations are available. Require equipment installers to consider carefully where and how each item of equipment is mounted in the interiors of vehicles to ensure that their installations will not impede the proper operation of safety belts or front or side air bag systems and installed equipment will not come loose and act as shrapnel in the event of collisions or rollovers or otherwise pose hazards to the driver or the passengers in the event of collision.

Air Bags
With the advent of air bags on both the passenger and driver sides of modern patrol vehicles, and with the proliferation of other types of air bags, such as doormounted side air bags and ceiling-mounted air bags, the mounting of specialized police equipment becomes even more difficult. Under no circumstances should these safety devices ever be disconnected, unless the passenger side is disengaged under the condition that there is absolutely no possibility a passenger ever will be transported in the right front seat and procedures are in place to ensure it once again is operational upon resale of the vehicle. The radio and other equipment should be placed at locations where the officer can readily access them without taking his or her eyes off the road. If that is impossible, then the position selected should be slightly lower so that the officer's sense of touch can guide him or her to the the controls needed. Many police equipment manufacturers now produce mounting racks that they claim are compatible with air bags.

Prisoner Transport Partitions
Equipping patrol vehicles with prisoner transport partitions (often referred to as transport cages) and roll bars provides safety for both the officers and any prisoner who is transported. Automotive engineers diagree about whether the installation of vehicle partitions adds needed rigidity to the vehicle or whether it defeats to some degree the vehicle's built-in crush zone, which is engineered to absorb a portion of the energy from an impact. It may be worth compromising the effectiveness of the crush zone somewhat to protect the officer from a prisoner who defeats the restraints and then attacks the officer while the vehicle is in motion. Prisoner transport partitions and side-curtain air bags are incompatible on the 2006 Chevrolet Impala, but both Chevrolet and Ford offer front-seat side-impact air bags that are compatible with prisoner transport partitions. Agencies considering the installation of prisoner transport partitions are encouraged to confer with vehicle manufacturers before installing them.

Items in the Trunk
The trunk of the police car requires special attention, too. Typically, the trunk will contain a crowbar, a shovel, a fire extinguisher, measuring devices, flares, first-aid kits, radio transmitters, in-car video camera controllers, and a variety of other specialized pieces of equipment. Some of these items have sharp edges, are installed with bolts or screws that have sharp edges, or are installed insecurely. In the event of a rear-end collision or a sudden stop, sharp-edged or insecure items can be catapulted forward and can penetrate the passenger compartment or puncture the fuel tank or fuel line, causing injury to the vehicle's occupants or, in the case of ignition, producing a flash fire or an explosion.

Studies of rear-end collisions where the fuel systems caught fire have indicated that in as many as one in three of these incidents items improperly stored in the vehicle's trunk punctured the fuel tank, and in another one-third a combination of items from the trunk and vehicle components compromised the integrity of the vehicle's fuel system. Of police agencies surveyed by the Arizona CVPI Blue Ribbon Panel, 85 percent said they had no policies or procedures for packing equipment in the trunks of their police vehicles.6 Specific suggestions for making the trunk safer are available.

  • Install items in the trunk of CVPIs as directed by Ford's trunk installation template that is downloadable for free from ( Make the template available to persons installing police equipment in the trunks of Crown Victoria Police Interceptors. Ford's publication "Trunk Packing Considerations" accompanies distributed copies of Your Vest Won't Stop This Bullet.

  • Make certain that items in the trunks of police vehicles are affixed firmly and are secured with fasteners strong enough to withstand crashes, so sharp-edged metal from flimsy clasps installed with inadequate bolts, nuts, or screws cannot puncture fuel system components.

  • Ensure that items such as crowbars, jacks and other heavy or sharp-edged items are stored laterally, with the points directed at the sides of the vehicle rather than fore and aft.

  • Provide secure trunk equipment containers, such as Ford's Trunk Pack designed for the Crown Victoria Police Interceptor, for the storage of items.

  • Cause vehicles' trunks to be inspected regularly by field supervisors to ensure that items are safely stowed.

Planning for the Lowest Common Denominator
When purchasing and installing vehicle markings and lighting systems, it is necessary to consider two factors:

  • Planning for the lowest common denominator

  • Deciding what message the department seeks to communicate

Planning for the lowest common denominator requires considering the entire audience that the department wants its message to reach. One of the most critical parts of this audience includes those drivers who are impaired, elderly and confused, fatigued, distracted, and young and inexperienced. Also, a department must ensure its message can be seen during the worst possible viewing conditions, the dark and rainy night and the glaring sunshine.

Even experienced police officers observe that sometimes when traveling in their personal vehicles and approaching several police or other emergency vehicles stopped at the roadside while handling an incident, the overabundance of dazzling, flashing, and pulsating lights makes it difficult for them to determine what is occurring and what they need to do: either to stop or to move safely past the incident. Often, officers directing traffic in dark uniforms without the benefit of high-visibility safety apparel are virtually invisible to drivers but nevertheless are frustrated when their signals are ignored. In some cases, improperly aimed take-down or alley lights that blind oncoming traffic exacerbate these situations.

Some researchers feel that too much lighting may cause a driver to momentarily turn in the direction of the light (the so-called moth-to-flame effect) rather than steer clear of it. If this message confuses even experienced police officers, imagine what it does to the lowest common denominator who may be driving while impaired or legitimately confused.

In recent years, the more-is-better philosophy has governed police vehicle lighting, but it may not be the most effective way to transmit the department's message to its audience. In fact, police vehicles most likely need to send two different types of warnings. The moving police vehicle on an emergency run seeking clearance through traffic needs to say, in effect, "Move over and let me through," while the stopped police cruiser at the roadside needs to say, "There is a hazard in the road, so slow down and move away from me." Two different types of lighting may in fact be required to convey these two disparate messages. Each situation requires that a single, clear message be sent, telling drivers what they are expected to do, because motorist-confusion can place officers at unnecessary risk.

State Patrol Studies
The Florida Highway Patrol and the Arizona Department of Public Safety have conducted experiments with emergency lighting and have made changes to their lighting systems based on the results of these studies. Research in Arizona favored the use of red and blue lights in conjunction with amber lights. That agency also favors rotating halogen lights over flashing strobes or LEDs (light emitting diodes) and multiple instead of single beams. Newer lighting technologies, such as LEDs, seem to hold considerable promise both for visibility without creating glare and for low current consumption where battery drain is a consideration. Photocells that sense the intensity of ambient light and modify the brightness of lights accordingly, can be helpful. Instructing officers to reduce the intensity of strobe lights when parked at the roadside, especially on dark, rainy nights, can also help reduce motorist confusion.

The California Highway Patrol has an admirable roadside safety record, despite having thousands of cruisers make millions of motor vehicle stops a year on some of the most highly congested and heavily traveled highways in the United States. It favors a minimalist approach to lighting: once the vehicle has been pulled over, only four-way flashers and lights to the rear are used.

Lighting Systems
When attempting to clear traffic on an emergency run, police vehicle lights should feature patterns of light intensity
and flashing or pulsating that will quickly catch the motorist's eye without blinding or confusing the motorist. Here is a case where more may actually be better, as long as the message being sent to the lowest common denominator is consistent and simplifies the driver's task of judging the size, speed, and direction of the oncoming emergency vehicle. Thought must also be given to the height of the warning device. It must be positioned high enough that it can be seen in a line of traffic yet low enough to be visible in the motorist's inside rearview mirror, bearing in mind that the traffic mix includes low sports cars and tall SUVs. However, grill-mounted lights, or those mounted on the backs of outside rearview mirrors, may be used to supplement roof lights to compensate for any loss of visibility.

Strobe Lights: Many departments that patrol areas experiencing considerable fog, rain, or other inclement weather favor strobe lights mounted on the exterior of vehicles. Strobe lights draw less current and are easier on batteries than halogen bulbs. However, unless strobe lights are properly aligned, they can temporarily blind both motorists and officers, and the flashes can interfere with certain sobriety tests. There also have been concerns that strobe lights flashing at quicker rates may trigger seizure-type disorders in some individuals. Devices are available to control the intensity of strobe lights.

Rotating and Flashing Lights: Any type of flashing light, including strobe lights, appears to be most effective when its pattern varies to some degree. Tests indicate that red lights are more visible in the daytime and that blue is more visible at night.

In most jurisdictions, state law controls the color of emergency lights and allocates certain colors to specific emergency services to help drivers distinguish between law enforcement, fire, emergency medical, and highway maintenance vehicles and wreckers.

Fiber-Optic Lights: The availability of fiber optics has made it possible to produce a variety of compact emergency lights that can be mounted in the rear window, on exterior rearview mirrors, and over the front windshield of police vehicles. These lights do not seem to produce the same amount of glare as strobe lights. Like strobe lights, they do not require a lot of electrical current to operate and seem to be very effective warning devices.

Takedown and Alley Lights: These lights, when mounted on a cruiser's light bar, enable officers to illuminate the interiors of vehicles during traffic stops, or the areas to the right and left of the police vehicle when checking alleys or commercial establishments. Great care must be taken in the installation of takedown lights to ensure that those lights will not blind oncoming motorists during roadside traffic stops. It is noteworthy that the Florida Highway Patrol activates simultaneously all of the forward-facing red and blue LEDs on its new lightbar, which translates into a nonglare off-white presentation the entire length of the lightbar.

Vehicle Markings
There are many schools of thought regarding the painting, striping, and coloring of police vehicles. Most agencies strive for distinctiveness: departments want their vehicles to be readily identified by the public and to instill a sense of pride in the department and the community. But safety should take precedence over distinctiveness. Installing high-quality reflectorized markings are an excellent way to increase a vehicle's conspicuity.

Striping should be of a highly reflective variety. The reflectorized areas should be large enough to command motorists' immediate attention; the Arizona DPS used all of the available bumper and trunk space as a billboard, not constraining its efforts to the size and quality of the reflectorized material used in the past. On the rear bumper of the police vehicle, an inverted chevron design similar to a highway barricade transmits the singular message to motorists that there is a hazard in the road ahead, and to drive safely around it.

On the sides of vehicles, it is most effective to outline the doors or the window frames with high-quality reflective materials so that drivers approaching from an angle recognize that what they are seeing is another vehicle and can judge the size of the police vehicle and give it a wide berth. Striping is as important as lighting, if not more so. Striping takes no power from the battery, is effective both day and night, and does not create glare or temporarily blind oncoming motorists. Of course, it is necessary that the vehicle be kept clean, because dirty striping loses much of its effectiveness.

The Arizona DPS found in its tests that the most visible colors for police vehicles are cream, white, and yellow. Statistics gathered by the International Association of Fire Chiefs seem to indicate that lime yellow fire trucks are struck less frequently than the traditional red apparatus.


In 1992 John M. Violanti's "Police Radar: A Cancer Risk?" concluded that police "officers must limit their exposure to radar electromagnetic fields (EMF) or departments must completely remove radar devices from police vehicles." Violanti's study suggests "a possible link between exposure to EMF and cancer."7 Quickly, the California Highway Patrol countered the Violanti report with its own studies.8 The California Highway Patrol studies concluded that there is no conclusive evidence to prove that the low levels of microwave radiation emitted from police radar devices are dangerous.

It is reasonable, however, for vehicles equipped with radar to include certain safety precautions and to prevent unnecessary exposure of officers to microwave radiation. Current information indicates that modern radar sets emit less radiation than cell phones or portable radios. However, it is still advisable to make sure that the radar antenna is always pointing away from the driver and passengers, and that handheld radar sets are turned off and stored on the seat when not in use, never in the lap of the driver. All radar equipment in the vehicle should be properly secured to protect the officer in the event of a crash or high-speed emergency operation.

The Florida Highway Patrol has developed a supplementary siren that uses a low-frequency signal (just above that of the car stereos one easily hears at traffic lights with all windows closed) to warn motorists of approaching emergency vehicles. It is less directional than traditional sirens and has increased by a minimum of 30 percent the distance at which a siren can be heard. Coupled with its new LED lightbar, the supplementary siren will increase the ability of motorists to detect the approach of police vehicles and is intended to increase the safety of all highway users.

The Future
This brief outline of items to be considered when equipping today's police vehicles is designed to help provide a safer work environment for officers. These suggestions resulted from careful thought by working groups of the Law Enforcement Stops and Safety Subcommittee (LESSS), as well as the IACP Highway Safety Committee. The committee will continue its work and report developments through the Police Chief magazine and its Web site, ( ■


1 J. H. Haager, "The Automobile as a Police Department Adjunct" (International Association of Chiefs of Police: Sixteenth Annual Session, Buffalo, N.Y., June 1518, 1909).
2 Bryan Vila and Cynthia Morris, A Documentary History: The Role of Police in American Society, (Westport, Conn.: Greenwood, 1999), 91.
3 Ford Motor Company. "Crown Victoria Police Interceptor: Police Officer Safety Action Plan," September 2002; (
4 International Association of Chiefs of Police, Highway Safety Committee, Law Enforcement Stops and Safety Subcommittee, "Staff Study" (Alexandria, Va.: 2004), 8.
5 International Association of Chiefs of Police, Highway Safety Committee, Law Enforcement Stops and Safety Subcommittee, "Staff Study" (Alexandria, Va.: 2004), 8.
6 Ford Motor Company, "CVPI Blue Ribbon Panel: Panel Topics-Updated" (2002); (
7 John M. Violanti, "Police Radar: A Cancer Risk?" FBI Law Enforcement Bulletin (October 1992): 14-16. Also see Kevin Morrison and Bob Jacob, "Speed Detection: From Mounted Antennae to Laser Technology," The Police Chief 67 (July 2000): 42-47.
8 Maurice J. Hannigan and Paul E. Crescenti, "The Effects of Police Radar Exposure: Another Perspective," The Police Chief 60 (July 1993): 53.



From The Police Chief, vol. 73, no. 1, January 2006. Copyright held by the International Association of Chiefs of Police, 515 North Washington Street, Alexandria, VA 22314 USA.

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