The Mansfield Bar: How a Tragic Crash Changed Trucking Safety Forever

June 29, 1967, a deadly collision in Louisiana claimed the life of Hollywood actress Jayne Mansfield. What seemed like another tragic accident quickly sparked a movement that would permanently change commercial vehicle safety. The result? A piece of metal attached to the back of trucks is known as the “Mansfield Bar.”

While most drivers have passed these bars on the road without thinking twice, few realize the devastating story behind their existence or how often they still fail to prevent fatal accidents today. At Coffey McPharlin, we represent victims of catastrophic truck accidents, including those involving underride crashes. We believe that awareness, accountability, and aggressive legal representation are critical to achieving justice.

What Happened to Jayne Mansfield?

Jayne Mansfield was riding in the front seat of a Buick Electra along with her driver, her lawyer, and three of her children when the car crashed into the rear of a truck that had slowed behind a pesticide spray city vehicle. The crash sheared off the top of the Buick, killing everyone in the front seat instantly. Her children, including future actress Mariska Hargitay, survived in the back.

The accident was horrific, and its image quickly spread through newspapers nationwide. Public demand for safety reforms surged as the country came to terms with a brutal truth: rear-end collisions with trucks could be instantly fatal, and they were far more common than many realized.

What Is an Underride Accident?

An underride accident occurs when a smaller vehicle slides under a large truck or trailer, usually a semi-truck usually during a rear-end or side-impact collision. Because the truck’s body is higher than a car’s crumple zones and windshield line, the result is often catastrophic head injuries or decapitation.

There are three main types of underride crashes:

  • Rear Underride: The most common occurs when a car collides with the back of a trailer.
  • Side Underride: Happens when trucks turn across traffic or change lanes.
  • Front Underride: Happens when a Truck runs over a smaller vehicle.

According to estimates from the National Highway Traffic Safety Administration (NHTSA), more than 400 fatalities occur each year due to underride collisions. However, safety experts argue that this number is underreported due to poor crash documentation and inconsistent data across agencies.

The Creation of the Mansfield Bar

After Jayne Mansfield’s death, safety advocates and regulators recognized the need to prevent future underride crashes. The proposed solution was straightforward: attach a horizontal metal guard to the back of trailers to prevent cars from sliding underneath.

These rear underride guards were eventually recommended by NHTSA, but adoption remained slow and inconsistent. It wasn’t until 1998 that the U.S. Department of Transportation made it a federal requirement for trailers to be equipped with rear guards meeting specific strength and height standards.

Though the regulations never officially named them, the public began referring to them as Mansfield Bars, a grim but important reminder of the tragedy that led to their creation.

Why Underride Crashes Still Happen?

Despite decades of advocacy and regulation, underride crashes continue to be a deadly problem on American roads. Why?

  1. Lack of side guards: Side underride guards are still not federally required in the U.S., even though they’ve been shown to prevent deadly crashes in urban areas and intersections.
  2. Weak or poorly maintained rear guards: Not all Mansfield bars are created equal. Some are made from insufficient materials, installed improperly, or allowed to rust and fail.
  3. Exemptions and outdated standards: Many trucks are exempt from rear guard requirements, and even regulated trailers may meet outdated specifications that don’t account for today’s vehicle speeds or crash dynamics.
  4. Enforcement gaps: Trucking companies may skip inspections or fail to replace damaged guards due to cost concerns or lack of oversight.

In short, while Mansfield Bars were a crucial first step, they’re far from a complete solution.

Legal Responsibility in Truck Underride Accidents

 

Underride trucking accident Car Under Trailer at Scene - Received from Police Officer Underride car crash with truck

 

When an underride crash occurs, it’s not just a tragic accident. It may be the result of negligence. Trucking companies are legally required to maintain their vehicles to federal safety standards. If a truck lacks a rear guard or has a damaged one, and that failure contributes to an injury or death, the company may be held liable.

At Coffey McPharlin, we aggressively investigate the following in underride crash cases:

  • Was the truck equipped with a compliant and intact rear guard?
  • Are there inspection and maintenance logs that show negligence or skipped service?
  • Did the trucking company use aftermarket or substandard safety parts?
  • Were side underride protections ignored in high-risk areas?

In some cases, third-party contractors, manufacturers, or even shippers may also share responsibility if their actions contribute to the risk.

Additionally, in fatal underride crashes, surviving family members may have grounds for a wrongful death lawsuit. These claims can recover compensation for funeral expenses, lost income, emotional trauma, and loss of companionship.

Coffey McPharlin: Fighting for Truck Accident Victims

Coffey McPharlin has earned a reputation for taking on high-stakes injury and wrongful death cases involving catastrophic failures, especially those that result from preventable safety lapses. We’ve gone head-to-head with large corporations and insurance companies to secure justice for clients who’ve lost everything in an instant.

If you or someone you love has been injured in a trucking accident. especially one involving a trailer underride team is prepared to investigate, advise, and take action.

Tragedy Turned into Reform, But More Work Is Needed

The Mansfield Bar is a powerful example of how a single event can drive policy change. But 50+ years later, it’s clear that more needs to be done. Underride crashes are still claiming lives. Too many trucks operate with broken or missing guards. Too many families are blindsided by the aftermath of what should have been a preventable disaster.

That’s why Coffey McPharlin continues to fight, not only in the courtroom but through education and advocacy. When companies cut corners on safety, we hold them accountable.

Need Help After a Trucking Accident?

If you or a loved one has suffered injuries or loss due to a trucking crash, especially involving an underride or failed trailer guard, don’t wait. Contact Coffey McPharlin today for a free, no-obligation case review.

Note: This article is for informational purposes only and is based on external sources. It is not legal or medical advice and does not constitute a business solicitation. The images included do not depict the actual scene. For corrections or removal requests, please contact Coffey McPharlin. 

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