Home » Put the Brakes on Runaway-Vehicle Defenses

Put the Brakes on Runaway-Vehicle Defenses

by Christopher L. Brinkley

Sudden acceleration nearly kept astronaut Neil Armstrong from his place in the history books. Three years before he walked on the moon, Armstrong piloted Gemini VIII’s March 1966 flight. Six and a half hours into the flight, the spacecraft’s maneuvering thrusters suddenly turned on and spun the capsule around both axes.

The accelerating spins were so violent that the situation quickly became life-threatening. Armstrong was not able to regain control of the spacecraft until he threw a circuit breaker, which disrupted the electrical power to the thruster system and disabled it. (1)

It is not likely that a potential client will ask you to handle a products liability claim regarding a malfunctioning spacecraft, but one may tell you, “when I shifted my car into gear, it took off on me. I didn’t touch the accelerator. In fact, I didn’t take my foot off the brake pedal.”

The potential client’s mechanic may tell you that nothing appears to be wrong with the car. He or she may say that cruise control can’t accelerate a car unless it is switched on and the car is already traveling at 35 mph, minimum. Since cruise control couldn’t have triggered the sudden acceleration, the mechanic will say, the driver must have stepped on the accelerator by mistake.

The auto manufacturer’s attorneys will respond to your notice of claim with a letter denying liability. They will state that the manufacturer has found no evidence of mechanical or electronic malfunction in any vehicle that could cause sudden acceleration. Sudden acceleration results from pedal misapplication, they’ll explain, and government studies support this conclusion.

You’ll check National Highway Traffic Safety Administration (NHTSA) reports on sudden acceleration. They will confirm the defense’s allegations.

The investigation seems pretty conclusive: The potential client must have inadvertently stepped on the wrong pedal.

Sudden-acceleration claims are among the most difficult to prove, and the pedal-misapplication argument is a struggle to overcome. In fact, that defense was successful in every electronic-defect case until 1996, when a plaintiffs verdict was finally rendered. (2) Since that time, approximately 10 more electronic-defect cases have resulted in verdicts against various auto manufacturers. (3)

The defense appeals to jurors because it is simple and because seemingly logical evidence supports it. Jurors know that applying the brake will not make a vehicle accelerate but that depressing the accelerator pedal will. Further, the vehicles involved usually yield no evidence of a malfunction, and investigations by the government and manufacturers conclude that driver error causes sudden acceleration.

Physical evidence in these claims often includes marks on the pedals, pedal brackets, and floorboard that indicate the accelerator pedal was depressed. Eyewitness testimony that the vehicle’s brake lights were not on can help substantiate that the driver did mistakenly apply the accelerator. When such evidence is not available (as is often the case), the manufacturer may mount this defense anyway.

In addition to–or in lieu of–evidence of the driver’s actions in a specific case, the defense may indict all drivers as being prone to making mistakes. The manufacturer will give examples of drivers who are most likely to step on the wrong pedal, including new vehicle owners and transient drivers (such as valets and car wash attendants), who are unfamiliar with the automobile; female drivers (although the manufacturer will offer no reason why the driver’s gender plays a role); young drivers; elderly drivers, who may have cognitive or motor deficiencies; and people who wear large shoes, which may hit both the brake and accelerator.

Although most of these observations seem well reasoned and innocuous, they imply that only small, middle-aged men who have driven their vehicles at least 50,000 miles are flawless drivers.

The defense will base the rest of its case on the argument that sudden acceleration cannot happen unless the accelerator is depressed. Learned engineers will testify that vehicles cannot suddenly accelerate on their own. They will say that numerous vehicle-testing reports show that neither preproduction nor postincident vehicle testing has revealed mechanical or electronic malfunctions that could result in sudden acceleration. The experts will testify that field investigation reports identify pedal misapplication as the cause.

The lone exception to the pedal-misapplication defense is the pedal-interference defense. The manufacturer may argue that the floor mats or some other object on the floorboard kept the accelerator pedal depressed. Or it may claim that an item on the floor such as a soda can prevented the driver from fully depressing the brake pedal.

When presented with a manufacturer’s relatively simple evidence–and drawing from the commonsense understanding that mistakenly applying the gas pedal will result in acceleration–jurors almost always slice and dice the plaintiff’s case with Occam’s Razor: When faced with two competing theories that explain the same event, the jurors will accept the simpler theory as the better one. They will disregard the plaintiffs complicated (and often unproven) theory of vehicle defect and conclude that the driver made a mistake and stepped on the accelerator.

It is imperative that you structure the plaintiffs case with the simple appeal of the defense in mind.

That appeal has been reinforced, although unintentionally, by the near-universal attempt to attribute all sudden accelerations to a single failure mode. This tunnel vision has plagued not only plaintiff investigations but also the efforts of the government, manufacturers, and consulting engineers. The fact is, sudden acceleration can be caused by pedal misapplication, vehicle design and operation, or numerous other factors. Despite whatever statistical trends exist, the cause of each event must be identified individually.

This is not to say that statistics are unimportant, just that you must exercise care to ensure that the cause of a specific incident is identified. Don’t let a statistical trend dictate–possibly erroneously–the cause of the incident.

Speed bumps

Plaintiffs and their expert witnesses have created obstacles for themselves by refusing to acknowledge that some sudden-acceleration incidents really are the result of pedal misapplication. Because a jury will not allow you to ignore the fact that people do make mistakes, you must be able to prove that pedal misapplication was not the cause or that the manufacturer is liable for the misapplication.

There are a number of possible defect theories:

* Mechanical failure. Kinked linkages, broken throttle-return springs, and other glitches may prevent the throttle from returning to idle.

* Design-induced pedal misapplication. When the vehicle’s pedals are too close together or shifted from the centerline of the steering wheel, drivers are more likely to misapply them. (4)

* Lack of a brake-shift interlock. This equipment, which is standard on most vehicles, forces the driver to depress the brake before shifting from park into gear. It has helped ensure that drivers do not misapply the pedals. However, it is effective only when shifting from park; sudden acceleration has occurred in vehicles equipped with the device when the drivers shifted from neutral to drive.

* Startle acceleration. When a driver is caught off-guard by a minor malfunction–such as a faulty idle-bypass valve, which can cause a relatively small amount of unexpected speed–he or she may inadvertently apply a pedal. (5)

* Faulty cruise control. Sometimes malfunctions in cruise-control systems can open the throttle without action by the driver. Intermittent faults can be caused by radio frequency or electromagnetic interference, signals from other engine components, transient circuits, short circuits, backfeeds, contamination, or corrosion. (6)

The essence of cruise-control faults is that electrical power reaches the cruise control servo in an unintended manner, which allows the servo to operate without input from the driver. The solution to virtually all cruise-control defects is to place a switch in the system that electrically isolates the servo unless the driver flips the switch.

The most critical decision a plaintiff must make when seeking to defuse the defense’s argument is which defect theory to use. Take extreme care to ensure that your theory is completely consistent with the case facts.

Your strategy must not be merely a shield; it must be a sword. If you can prove that the manufacturer’s theory ignores certain facts, you can undermine its appeal and show the jury that the manufacturer has engaged in willful misconduct by consistently disregarding the facts in its sudden-acceleration investigations.

Questions to consider

Jurors have identified the queries following as the most important ones in determining the cause of sudden acceleration. The questions and answers, in order of importance:

* Did the driver say his or her foot was on the brake? Beware the driver who says, “The harder I pushed the brake, the faster the vehicle went.” If a driver steps harder on a pedal and the vehicle accelerates, jurors are likely to conclude that the driver must have been depressing the accelerator. In contrast, a driver who says both feet were on the brake undermines the pedal-misapplication defense: There isn’t room on the gas pedal for two feet.

Also, be careful with the issue of brake failure. The manufacturer will attempt to make the driver say the brakes failed. If inspection reveals no mechanical malfunction in the brakes, the manufacturer will argue that the forensic evidence is not consistent with the driver’s testimony, and that if the driver really had been applying the brakes, the vehicle would have stopped.

The key here is that most sudden-acceleration cases involve not brake failure but reduced brake effectiveness. (7) When a car suddenly accelerates, the driver takes a second or two to react. Then he or she depresses the brake, only to find that the vehicle does not stop as quickly as expected.

This occurs primarily) because the engine is still accelerating the vehicle or because there is insufficient vacuum assist for the brakes. The brakes work, but they require increased pedal force and increased stopping distance. In some cases, the driver’s leg may not be strong enough to apply the required force. (8) Because the stopping distance is increased, many sudden accelerations end in a collision before the driver can stop the vehicle.

* Did a witness see brake lights? If the brake lights were on, the driver must have had at least one foot on the brake pedal. The manufacturer will claim that brakes will always overpower the engine, so the vehicle should have stopped even if the driver had been inadvertently applying the accelerator as well as the brake.

Manufacturers frequently try to undermine the testimony of brake-light witnesses by claiming that if the brake lamps were on when the car crashed, the lamp filaments would have been distorted. The likelihood of lamp distortion, or “hot shock,” is greatly reduced when the point of impact is more than a few feet from the lamp. (9) In frontal collisions–the most common sudden-acceleration crashes–filament distortion is unlikely on brake lamps.

* Does the accelerator pedal or pedal bracket bear any marks that could indicate pedal error? If a driver slams the accelerator pedal into the floor instead of the brake pedal, the accelerator pedal or the pedal bracket may be deformed at the point of contact. Such damage is powerful evidence purchase electronic cigarettes of pedal misapplication. If there is evidence of contact between the bracket and the pedal but no significant indentation, the mark is probably from ordinary use.

* Was the engine racing before the driver put the vehicle in gear? If the driver heard the engine racing, jurors often find that he or she should have been alerted to a problem and should not have put the vehicle in gear. If the driver did not hear the engine racing, the manufacturer will frequently say that the vehicle’s insulation, radio, or air conditioner and heat blower prevented him or her from doing so. A witness who was not in the vehicle can prove helpful for plaintiffs.

* Did the vehicle leave tire marks? Most vehicles do not leave acceleration marks on pavement unless the engine is at wide-open throttle when the brakes are released. (10) Most cruise controls cannot create sufficient power to make the car leave such marks.

* Is there any evidence that the cruise control, engine controller, or other component malfunctioned? Look for fault codes in the engine controller or physical evidence on the vehicle itself. A fault code is set when the engine malfunctions in a way that the engine computer recognizes as a failure. System failures that bypass the logic functions of the engine controller, such as a wiring-harness short, often elude the fault system. In addition, fault codes are often absent after a sudden acceleration, as a vehicle’s battery frequently becomes unplugged after the incident.

Although there may be no diagnostic evidence of a malfunction in a sudden-acceleration case, there may be circumstantial physical evidence of the failure. For example, pedal misapplication usually results in a wide-open throttle. Most cruise controls can open the throttle plate only 70 percent. If throttle-cable damage indicates that the throttle was 70 percent open at impact, you can make a strong argument that a cruise-control malfunction–rather than pedal misapplication–caused the acceleration.

Other circumstantial evidence may include fluid leakage near or on the engine controller, loose wiring harnesses, frayed electrical wiring, or corrosion of the wiring harnesses or engine controller.

Another way to undermine the defense is to introduce evidence of other similar incidents. (11) This will show the jury that your client’s experience is not unique. In cases based on electronic defects, similar incidents show how far an auto manufacturer will go to disavow any evidence of a mechanical or electronic malfunction.

Similar incidents can also refute a manufacturer’s claim that it is impossible for a vehicle to suddenly accelerate as a result of a defect. They also illustrate the magnitude of the defect in a punitive damages argument.

As a general rule, the best witnesses for this tack are the automaker’s corporate employees and car dealers; highly trained drivers, such as law enforcement officers; drivers whose professions are based on unquestionable integrity, such as judges and clergy; and drivers who must exercise extraordinary care, such as those who pass through school zones, take part in funeral processions, navigate steep driveways, and park beside cliffs. It is often difficult for the defense to effectively cross-examine these witnesses.

Diminished defenses

As mentioned above, government studies finding that sudden acceleration results from pedal misapplication are a corner-stone of the defense. In the minds of many jurors, a government investigation by an agency that is responsible for protecting the public from unsafe vehicles is conclusive on the issue of defect.

Unfortunately, government studies are usually hampered by politics, lack of funding, and manufacturers’ failure to disclose all relevant information. (12) In addition, these studies’ definition of “sudden acceleration,” as well as the bases for some of the experiments and analyses, are often questionable and virtually dictate the outcome. As a result, the conclusion–particularly with regard to electronic defects–are highly suspect.

In most cases, these studies have not examined the vehicle at issue in your case. A motion in limine stating that the vehicles that have been studied are not substantially similar to your client’s vehicle can usually get the reports excluded. If they do come into evidence, contest them during cross-examination. By challenging these studies, you reduce the appeal of the defense by removing its imprimatur of government authority.

One of the best ways to refute the defense is through discovery of corporate documents that show the automaker knew or should have known of the defect. (13) You should discover the following documents in all sudden-acceleration cases:

* Similar-incident reports. These include lawsuits, legal claims, warranty claims, customer and dealership inquiries, arbitration-board records, and lemon-law records. The documents not only provide the foundation for similar-incident testimony but also are necessary for any detailed statistical analysis.

* Operator’s and service manuals. Warnings and diagnostic fault trees (pictograph flow charts) in a vehicle’s manuals often reflect a manufacturer’s knowledge of sudden acceleration.

* Studies and minutes of company meetings that discuss sudden acceleration. These documents provide insight into the company’s sudden-acceleration information-gathering and evaluation process, what it pays attention to and what it ignores, how it chose to address the sudden-acceleration problem, and its motivations in making that decision.

* NHTSA correspondence. The federal government has made several inquiries to automakers about sudden acceleration. Correspondence that indicates what the manufacturer told the government, and what it did not, can provide powerful evidence that may convince the jury to award punitive damages.

* Brake-shift-interlock design materials. The brake-shift interlock was designed to “prevent” sudden acceleration. Documents about its design reveal what the manufacturer knows about sudden acceleration-and that the interlock reduces the sudden-acceleration claim rate but does not stop the problem.

The following discovery materials are important in electronic-defect cases:

* Failure Modes and Effects Analysis (FMEA) documents. Manufacturers perform FMEA analyses on virtually every vehicle part and system. Design engineers brainstorm every possible way the part or system can fail, and they determine the potential effects of those failures. In many instances, the manufacturer tests the potential failures. Documents that show FMEAs were conducted on a vehicle’s cruise control, engine controllers, and wiring harnesses frequently reveal that the manufacturer knew of potential malfunctions and their consequences.

* Performance- and quality-testing documents. These include electromagnetic and radio-frequency tests, as well as fluid and particulate-matter-contamination testing of electronic hardware and harnesses. The materials often show that the manufacturer performed inadequate tests, particularly if FMEAs identified any failure modes.

In design-induced pedal-misapplication cases, counsel should discover the following information:

* Pedal-package drawings, competitive-vehicle studies, and minutes of related meetings. These documents show how unusual pedal layouts can cause drivers to press the accelerator by mistake.

* Human-factors studies and subjective vehicle evaluations. Manufacturers often study driver behavior as part of pre-sale vehicle analysis. Vehicle-operation observations, studies of drivers entering and exiting vehicles, and other similar materials can prove corporate knowledge of the potential for inappropriate driver behavior.

Using experts

Plaintiff experts’ inability to precisely identify the cause of cruise-control malfunction-and their failure to conduct tests that show how the alleged defect may have activated the cruise control–can enhance the appeal of the manufacturer’s defense. Such shortcomings often result in experts’ testimony being excluded under Daubert v. Merrell Dow Pharmaceuticals, Inc. (14) Keep in mind the following considerations when seeking an expert for a case that alleges an electronic defect:

* Hire an electronics expert. General automotive experts often do not have the expertise to properly evaluate complex electronics issues.

* Make sure that your expert not only makes a theoretical analysis but also thoroughly examines the vehicle for physical evidence that supports his or her opinions, even if the evidence is only circumstantial. Jurors will be skeptical of a malfunction that leaves no evidence. You must be able to point to something in the vehicle and say, “This shows what went wrong.” A forensic engineer can be a wise investment in this regard.

* Have your electronics expert conduct tests showing that the alleged failure modes really do occur. Recent, in-depth testing of vehicle electronics by several different experts can provide concrete evidence of the systems’ susceptibility to inadvertent actuation. Nothing carries more weight with the jury than seeing the failure occur. (Although the vehicle and equipment may be too large to present in court, component mock-ups can be effective.)

Your testing has two other benefits: First, it lets you challenge the defense testimony about all the tests the manufacturer conducted. Second, the manufacturer will not demonstrate for the jury any electronics test where a failure actually happens. When your expert runs a test and a failure occurs, the jury will pay attention and give it greater weight.

Challenge the appeal of the manufacturer’s defense by helping the jurors personally relate to your defect theory. For instance, most people have used a computer, and most have worked on a PC that at least once has locked up; added, deleted, or jumbled text; corrupted files; or failed in some other way.

Engine controllers that govern cruise control are computers. They are subject to the same hardware and software failures as personal computers. By drawing analogies, you help the jurors grasp the essence of your client’s case.

Simply refuting the validity of a defense will seldom convince a jury. However, when the simplicity and common sense of the defense argument appeal to the jury, your failure to address the defense can be equally fatal.

Plaintiffs can carry their burden of proof by demonstrating the cause of the acceleration. Those who do so can undermine the appeal of the pedal-misapplication defense-and win.


(1.) BARTON C. HACKER & JAMES M. GRIMWOOD, ON THE SHOULDERS OF TITANS: A HISTORY OF PROJECT GEMINI (1977), available at www.hq.nasa.gov/office/pao/History/SP-4203/ch13-6.htm.

(2.) Selman v. Ford Motor Co., No. PB-C-94-474 (E.D. Ark. Oct. 15, 1996).

(3.) See, e.g., Jarvis v. Ford Motor Co., 69 F. Supp. 2d 582 (S.D.N.Y. 1999), aff’d, Nos. 99-9405(L), 00-9215(CON), 2002 WL 188480 (2d Cir. Feb 7., 2002); Santosa v. DaimlerChrysler Corp., No. 97-2-25547-3 SEA (Wash., King County Super. Ct. Apr. 12, 2001).


(5.) POLLARD, supra note 4, at 41.

(6.) See generally Samuel J. Sero, Sudden or Unwanted Acceleration in an Automobile, in 1 ATLA 2001 Annual Convention Reference Materials 1277 (2001).

(7.) POLLARD, supra note 4, at 17.

(8.) Id. at 17, 49.


(11.) See generally Tab Turner, Proving Design Defects with Other Similar Incidents Evidence, TRIAL, Mar. 1999, at 42.

(12.) Allan J. Kam, NHTSA Safety Defect Investigations, in 2 ATLA 2001 Annual Convention Reference Materials 2521 (2001).

(13.) See generally Christopher L. Brinkley, An Overview of Jeep (DaimlerChrysler) Sudden Acceleration, in 1 ATLA 2001 Annual Convention Reference Materials 1249 (2001); Molly S. O’Neill, Faulty Cars or Faulty Drivers? The Story of Sudden Acceleration and Ford Motor Company, in 1 ATLA 2001 Annual Convention Reference Materials (2001).

(14.) 509 U.S. 579 (1993).

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