By Tim Dees
Once you have decided you need to be in a pursuit, you need to set about ending it. You can hope that the evader will run out of gas or stack the car up (hopefully, hitting something inanimate and not too expensive), but affirmative measures are usually called for.
Police resources are finite. You can’t chase the guy forever. There are also risks associated with the various methods of ending pursuits, from the possibility of allowing your suspect to escape on the low end to endangering the lives of officers or bystanders with more decisive methods.
Every decision to end a pursuit has to be balanced against the potential risk. This risk is most easily reduced by ensuring that everyone involved in ending the pursuit has appropriate training, and that they are confident in their skills.
One high-tech approach to ending pursuits is StarChase. Patrol vehicles equipped with StarChase have a compressed air-powered launcher installed on the front of the car. On command from a dashboard console or a remote key fob, the launcher shoots a GPS tracker with an adhesive cap toward the suspect vehicle. The tracker “tag” sticks to the car body and starts transmitting location and direction of travel data to a base station. Officers track the vehicle and move in for the arrest when the tactical situation best favors them.
Each launcher holds two tags. Lateral aiming is controlled by the steering of the patrol car, but the operator can adjust elevation from the console. StarChase also supplies inert training tags to reduce the cost of getting officers up to speed on the system.
If you’re fortunate enough to have a police aircraft overhead, you can track the suspect until he gets to a place he can be blocked in, or he leaves the vehicle. Then, patrol units come in and finish off the operation.
Unfortunately, air support units are so expensive that only the largest agencies have them available around the clock, and most have no air support at all. It probably won’t be too many years before more affordable unmanned aircraft, drones, become available for prosecuting pursuits and other tracking operations. For now, there is a range and licensing barrier with most models.
Precision Immobilization Technique (PIT)
Officers trained in the PIT maneuver their cars so that their right or left bumper is even with the spot behind the evader’s rear wheel well, then strike the evading vehicle with force 90 degrees to the direction of travel. Done correctly, the evading vehicle will spin out of control, coming to rest facing 180 degrees from the original direction of travel. The driver’s disorientation and car positioning allow officers to block the evader in and apprehend the suspects.
PIT was developed by the Fairfax County (VA) Police Department in the mid-1990s. Done right, a PIT maneuver is a thing of beauty. However, training officers in PIT is time-consuming, tends to cause damage to training vehicles, and is a degradable skill, requiring refresher training from time to time. The officer needs to pick a good location that will not cause excessive damage or loss of life, and speeds generally must be below 35 MPH at time of impact. It doesn’t work as well on newer vehicles with electronically controlled anti-skid systems. For all these reasons, many agencies do not train their officers in PIT, and some forbid its use explicitly.
Various tire spike products have been in use since their introduction in the early 1990s. These are usually embedded into strips ranging from three to 20 or more feet long that are placed in the path of the pursued vehicle. The spikes are hollow and are designed to break off as they pierce the tires, deflating them gradually. There are other products that shred the tires catastrophically, but such failures can be deadly at high speeds.
Tire spikes have been instrumental in ending many pursuits, but some of the less successful deployments have been tragically spectacular. Drivers whose tires have deflated and disintegrated have driven for miles on the metal rims, sparks flying behind them. The spikes slow the cars down, but they seldom stop them. Worse, officers who deploy the spikes must put them out seconds before the suspect vehicle passes, and become targets for the evader. In 2011 alone, five U.S. law enforcement officers were killed deploying tire spikes.
A more effective variation on the tire spike design builds the spikes into the leading edge of a durable fabric mat. The spikes embed into the car’s tires and the momentum wraps the mat around the wheels. The mat is made of Dyneema fabric, which is also used in police body armor, and has a higher tensile strength than steel.
When the mat wraps around the wheels, it fouls the carriage and the wheels stop turning. The car comes to a stop as fast or faster than if the driver stood on the brake. There are several online videos that demonstrate the effectiveness of the arresting mat.
One arresting mat manufacturer is QinetiQ Group PLC, a British defense materiel contractor. Their arresting mat product is called X-Net, and is used by the U.S. Army, among others. X-Net can be deployed via remote control, or simply laid onto the pavement by the user. The mat is made of a dark material and is harder to see and avoid than spike strips.
If the arresting mat is a variation on tire spikes, then The Grappler is a similar variation on the arresting mat. Grappler-equipped police vehicles have the equipment mounted on the front bumper of the patrol car. On command, a Y-shaped bracket extends up and then out from the front of the patrol car, held a few inches above the pavement surface. Between the arms of the “Y” is a fabric netting material. The officer maneuvers the bracket onto the rear wheel of the evading vehicle, snagging the fabric on the wheel.
The fabric wraps around the evader’s wheel, immobilizing it and bringing the car to a stop. The fabric net is still tethered to the patrol car, so even if the fleeing vehicle continues to try and move, it won’t get far. The tether can be released at any time. The manufacturer warns that using The Grappler on a front-wheel drive car will only flatten the tire, not immobilize the vehicle. They recommend using the tether in this situation.
One possible concern is that the patrol car equipped with The Grappler must get within a few inches of the fleeing vehicle to get the net under the tire. If the suspect was to brake at that moment, the result might be disastrous. The Grappler is a new product, and the company’s promotional materials do not list any deployments with law enforcement agencies.
Pursuit policies need to be all-encompassing and integrated, covering the circumstances under which the pursuit is undertaken, and including the measures that may be used to end it and when they can be deployed. Training should be ongoing, not limited to a few hours in the academy or an in-service block. Policies and methods are good material for roll-call training. When there is an occasional quiet shift or training day, consider breaking out the tire spikes or other gear for some refresher work in the field.
The setting where a pursuit may be necessary is all but inevitable, and it will come without warning. Consider whether you are prepared for this.
About the author
Tim Dees is a retired police officer and the former editor of two major law enforcement websites who writes and consults on technology applications in criminal justice. He can be reached at firstname.lastname@example.org.