The rate of pursuit is both a physical measurement of how fast a police vehicle travels during a chase and a statistical measure of how often an agency chooses to pursue rather than let a driver go. Both meanings exist for the same reason: between 2009 and 2023, police pursuit crashes in the United States killed an average of 423 people a year, and roughly 30 percent of those killed were bystanders with no connection to the chase.1JAMA Network Open. Police Pursuit Fatalities in the US, 2009 to 2023 Every rule discussed below, from when a chase can start to who can be sued when it ends badly, flows from that casualty count.
What the Term Actually Measures
In its physical sense, the rate of pursuit is the speed and acceleration a patrol car maintains while chasing a fleeing vehicle. Officers track their velocity against the suspect’s vehicle and the surrounding traffic, adjusting for curves, intersections, and road conditions. Sustained high speeds increase the risk of mechanical failure, lengthen stopping distances, and compress reaction times.
The statistical rate works differently. It compares the number of chases an agency initiates against total enforcement contacts in the same period. A department that runs 1,000 traffic stops and pursues 10 fleeing drivers has a pursuit rate of 1 percent. Administrators use that figure to spot trends, compare units or shifts, and test whether a policy change actually changes behavior on the street. A rising rate can signal a training gap or a shift in local crime; a falling rate can reflect tighter policies or better access to tracking technology that lets officers back off.
The Casualty Picture
Between 2009 and 2023, the United States recorded 5,425 fatal motor vehicle crashes tied to police pursuits, averaging about 362 fatal crashes a year. Those crashes involved more than 8,300 vehicles and killed 6,352 people.1JAMA Network Open. Police Pursuit Fatalities in the US, 2009 to 2023 The dead include fleeing suspects, pursuing officers, passengers in either vehicle, and people who happened to be on the road or sidewalk at the wrong moment. About 30 percent of pursuit fatalities are bystanders with no connection to the underlying crime.2JAMA Network Open. Police Pursuit Fatality Rates in the US and Future Research Directions
That bystander figure is the single biggest force shaping modern pursuit policy. When a chase kills a third party, the political and legal fallout dwarfs whatever offense triggered the stop in the first place. It is also why departments increasingly restrict pursuits to violent crimes.
When Officers Are Allowed to Pursue
Agencies generally fall into one of three policy categories. A discretionary policy leaves the major decisions, whether to start, continue, and end a chase, to the officer’s real-time judgment. A restrictive policy limits pursuits to specific crime categories or threat levels and overrides individual judgment. A discouraging policy actively discourages any pursuit except in the most extreme circumstances, such as an active violent threat to the public.
Over the past two decades, the trend has moved firmly toward restrictive policies.3Office of Justice Programs. Restrictive Policies for High-Speed Police Pursuits A joint guide from the Department of Justice’s COPS Office and the Police Executive Research Forum recommends that agencies authorize pursuits only when two conditions are both met: a violent crime has been committed, and the suspect poses an imminent threat to commit another violent crime. If either condition is absent, officers should use alternatives to apprehension.4COPS Office, U.S. Department of Justice. Vehicular Pursuits – A Guide for Law Enforcement Executives The guide draws one distinction that trips up a lot of people: the danger justifying a pursuit must come from the suspect’s underlying criminal conduct, not from the reckless driving the suspect does while fleeing. A driver doing 90 in a school zone to escape a traffic stop is obviously dangerous, but under restrictive policies that escalating risk is a reason to call the chase off, not a reason to keep going.
Most restrictive policies draw a hard line between violent felonies and everything else. Aggravated assault, armed robbery, kidnapping, and homicide generally justify a pursuit. Property crimes, misdemeanors, and traffic infractions generally do not, even if fleeing itself technically creates a new offense. The reasoning is practical: if the driver’s identity is already known or a license plate is captured on camera, the arrest can wait.
Managing the Rate in Real Time
A pursuing officer is operating on adrenaline and incomplete information. Most departments require a supervisor to monitor every active pursuit from a detached position, typically through radio traffic and GPS tracking, with authority to terminate at any point. That second set of eyes catches what the officer behind the wheel cannot: the chase has entered a residential neighborhood, the suspect is slowing down, or the offense does not justify the escalating danger.
Officers are expected to feed a continuous stream of information to dispatch: location, direction, speed, traffic density, weather, road conditions, a description of the suspect vehicle and its occupants, and a running account of the suspect’s driving. Dispatch coordinates other units, clears intersections along the projected path, and feeds the supervisor the information needed to make termination calls.4COPS Office, U.S. Department of Justice. Vehicular Pursuits – A Guide for Law Enforcement Executives When a pursuit crosses jurisdictional lines, most neighboring agencies operate under mutual aid agreements that grant “fresh pursuit” authority. The pursuing agency notifies the agency whose territory the chase has entered, and that agency either takes over, provides support, or asks for a termination.
How Officers End a Pursuit
Departments that permit pursuits also regulate how officers can stop them. The tools fall into a few categories.
Vehicle Contact
The Pursuit Intervention Technique, known as the PIT maneuver, uses the patrol car to push the suspect’s rear quarter panel and spin the fleeing vehicle to a stop. Most agencies restrict PIT maneuvers to speeds below a set threshold, often 35 to 45 miles per hour, because at higher speeds the technique can cause rollovers. Some departments prohibit it entirely.
Tire deflation devices, commonly called spike strips, go on the road ahead of the fleeing vehicle. Hollow spikes puncture the tires and cause a gradual deflation. Officers deploying them have to position themselves well off the road and coordinate with the pursuing units so patrol cars avoid the strips. The goal is a controlled slowdown, not an abrupt stop.
GPS Tagging
GPS pursuit technology takes a different approach. A compressed-air launcher mounted on the patrol car fires a small GPS tracker that attaches to the suspect’s vehicle. Once tagged, the officer can back off, kill the lights and sirens, and track the vehicle remotely. Early case studies of the StarChase system found that tagged suspects slowed to within 10 miles per hour of the speed limit in under two minutes, with an apprehension rate above 80 percent and no injuries, fatalities, or property damage.5GovInfo. Pursuit Management – Fleeing Vehicle Tagging and Tracking Technology Field results have been more mixed. Some agencies report trouble getting tags to attach at high speed, and suspects occasionally find and remove them. The technique works best when the suspect does not realize they have been tagged, which requires the officer to back off quickly.
Aerial Tracking
Drones and helicopters let officers track a fleeing vehicle without maintaining a ground pursuit. Drones reach the scene faster than helicopters and can follow a suspect from overhead while ground units hold back. The aerial view also informs decision-making by showing whether the suspect is approaching a school, a highway, or a dead end. Several departments have expanded drone programs specifically to reduce reliance on high-speed ground pursuits.
When Termination Becomes Required
Environmental conditions are the most common trigger for ending a chase. Heavy pedestrian traffic, school zones, hospital campuses, construction areas, and residential neighborhoods raise bystander risk beyond what most policies allow. Rain, ice, fog, and darkness increase stopping distances and reduce visibility for everyone on the road.
The strongest argument for calling off a chase is that the driver’s identity is already known. Once a license plate is captured and the suspect is confirmed through database queries, the immediate justification for a high-speed pursuit evaporates. Officers can obtain a warrant and make the arrest later. Termination also applies when the pursuing officer loses visual contact: continuing at pursuit speeds without knowing where the suspect is creates all the danger of a chase with none of the benefit. Most policies require the officer to slow to the posted speed limit immediately and return to normal patrol status.
The Constitutional Rules
Three Supreme Court decisions set the legal frame for police pursuits. Each answers a different question: when does a pursuit become a seizure, how much force is reasonable to end one, and what standard applies when someone else gets hurt.
When a Pursuit Becomes a Seizure
Chasing a car with lights and sirens is not, by itself, a Fourth Amendment seizure. In California v. Hodari D., the Supreme Court held that a seizure requires either physical application of force or the suspect’s actual submission to the officer’s authority. An officer yelling “stop” at someone who keeps running has not seized that person.6Legal Information Institute. California v. Hodari D. The practical result: Fourth Amendment protections kick in only when the officer physically contacts the fleeing vehicle or the driver pulls over.
Reasonable Force to End a Chase
Once a pursuit does become a seizure, the question is whether the officer’s actions were reasonable. In Scott v. Harris, an officer rammed a fleeing driver’s car off the road at high speed, leaving the driver a quadriplegic. The Supreme Court held that the Fourth Amendment does not prohibit an officer from using force to end a dangerous high-speed chase, even if that force puts the fleeing driver at risk of serious injury or death.7Justia Law. Scott v. Harris, 550 U.S. 372 (2007) The test weighs the severity of the intrusion on the suspect’s rights against the threat the suspect poses to others. Dashcam video showed the driver weaving through traffic, running red lights, and forcing other cars off the road, which made the ramming reasonable.
The Court extended that reasoning in Plumhoff v. Rickard, holding that officers who fired 15 shots into a car to end a pursuit that reached speeds over 100 miles per hour did not violate the Fourth Amendment. Once a fleeing driver creates a genuine threat to others, officers can meet that threat with proportional force.8Justia Law. Plumhoff v. Rickard, 572 U.S. 765 (2014)
A related principle comes from Tennessee v. Garner, which held that officers cannot use deadly force against a fleeing suspect unless the suspect poses a significant threat of death or serious physical injury to the officer or others. That case involved an officer shooting an unarmed teenager in the back as he fled a burglary, and the Court struck down blanket policies authorizing lethal force against all fleeing felons.9Justia Law. Tennessee v. Garner, 471 U.S. 1 (1985) Its proportionality framework runs through every pursuit case that followed.
The Standard When a Bystander Is Hurt
When a pursuit injures or kills someone who was never the target, the legal analysis shifts from the Fourth Amendment to the Fourteenth Amendment’s due process clause. In County of Sacramento v. Lewis, a pursuing officer’s motorcycle struck and killed a passenger on the suspect’s bike. The Supreme Court held that recklessness, or even gross negligence, is not enough to establish a constitutional violation in the pursuit context. Because officers in high-speed chases make split-second decisions under extreme pressure, only conduct driven by a “purpose to cause harm unrelated to the legitimate object of arrest” crosses the constitutional line.10Justia Law. County of Sacramento v. Lewis, 523 U.S. 833 (1998) That bar is extraordinarily high. Most pursuit injuries to bystanders, no matter how tragic, will not clear it.
Civil Liability After a Pursuit
When a pursuit injures or kills someone, the legal aftermath often costs the agency far more than the original crime would have. Lawsuits against officers and their departments typically arise under 42 U.S.C. ยง 1983, which allows anyone whose constitutional rights were violated by a government actor to sue for damages.
Claims by the Suspect
A suspect injured when an officer uses force to end a chase brings a Fourth Amendment excessive-force claim. Under the Scott v. Harris framework, the court balances the threat the suspect posed to the public against the severity of the force used. If the suspect was weaving through traffic at high speed, the balance tips sharply toward the officer. If the suspect was driving normally and the underlying offense was minor, the calculus shifts.7Justia Law. Scott v. Harris, 550 U.S. 372 (2007)
Claims by Bystanders
Bystanders face a much steeper legal climb. Because no seizure of the bystander occurred, the Fourth Amendment does not apply. The bystander must instead show a Fourteenth Amendment due process violation, which requires proving the officer acted with a purpose to cause harm unrelated to the arrest. Negligence, recklessness, and even gross negligence are not enough.10Justia Law. County of Sacramento v. Lewis, 523 U.S. 833 (1998) That standard makes federal constitutional claims by bystanders extremely hard to win.
Municipal Liability
Injured parties can also sue the municipality itself if the department’s pursuit policy was so deficient that it amounted to deliberate indifference to constitutional rights. That requires showing either that the need for better training or policy was obvious, or that a pattern of similar incidents put the department on notice and it failed to respond. If no individual officer violated the Constitution, there is no municipal liability, so these claims rise or fall on the underlying constitutional analysis.
Qualified Immunity
Even when an officer’s conduct does violate a constitutional right, qualified immunity can shield the officer from personal liability. The defense works in two steps: did the officer’s actions violate a constitutional right, and was that right “clearly established” at the time of the pursuit, meaning prior court decisions had already told a reasonable officer that this specific conduct was unlawful?7Justia Law. Scott v. Harris, 550 U.S. 372 (2007) In high-speed pursuit cases, the “clearly established” prong is hard for plaintiffs to clear because the fact patterns vary so widely. Many state tort claims also face sovereign immunity caps that limit how much a plaintiff can recover from a government entity, though those caps vary by state.
Reporting and Data Collection
Once a pursuit ends, the administrative work begins. Officers complete detailed reports covering the reason for the initial stop, the reason the suspect fled, the duration and distance of the chase, maximum speeds, intervention techniques used, and the final outcome: arrest, crash, voluntary stop, or escape. Most agencies require those reports within 48 hours.
The COPS Office and the Police Executive Research Forum recommend that agencies track and publish specific data points annually:
- Total pursuits initiated during the reporting period.
- The underlying offenses that prompted each pursuit.
- How many pursuits were called off by officers or supervisors before apprehension.
- How many pursuits resulted in crashes, injuries, deaths, or property damage.
- How many fleeing drivers were identified even when the chase was terminated.
- How many drivers fled but were not pursued.
- How many pursuits were found to be within policy during administrative review.
Those recommendations come from the same DOJ-backed guide that defines the restrictive pursuit model.4COPS Office, U.S. Department of Justice. Vehicular Pursuits – A Guide for Law Enforcement Executives No federal law requires agencies to follow them. There is no national database of police pursuits comparable to the FBI’s Uniform Crime Reporting system. Some states mandate pursuit data submission within 30 days; others have no reporting requirement at all. The result is a patchwork of local data that makes national trends hard to measure and cross-agency comparisons nearly impossible.
Property damage and injuries are documented separately to support potential civil claims. Suspects apprehended after a pursuit typically face evasion charges on top of whatever offense triggered the original stop, and those charges vary widely by jurisdiction, from misdemeanor penalties of less than a year in jail to felony sentences of several years.
Training Behind the Rate
Officers learn pursuit driving through Emergency Vehicle Operations Courses, known as EVOC. These programs teach the mechanical skills of high-speed driving: skid control, high-speed cornering, threshold braking, and clearing intersections with lights and sirens active. The underlying philosophy goes beyond car control. A well-designed EVOC program is meant to make officers aware of the limits of their ability and their vehicle, not to build overconfidence.11Office of Justice Programs. Pursuit Driving for Law Enforcement Officers Mandatory training hours vary widely across states, from as few as two hours to as many as 80.
Driving simulators have become an increasingly important supplement to track-based training. Simulators let officers practice high-risk scenarios, a suspect swerving into oncoming traffic or a pedestrian stepping into the road, without real-world danger. Research suggests simulator training reduces the negative effects of multitasking under stress and improves overall driving performance in emergency situations. Simulators also let pursuing officers and supervisors train together, practicing the communication and decision-making that define a real pursuit. The main limitation is that no training environment can fully replicate the chaos of a real chase, where suspect behavior is unpredictable and the stakes are permanent.