The Mansfield Bar: How a Celebrity Death Changed Auto Safety

The shocking death of actress Jayne Mansfield 56 years ago today led to changes in the trucking industry, but underride crashes continue to kill hundreds of people each year.

3 minute read

June 29, 2023, 12:00 PM PDT

By Diana Ionescu @aworkoffiction


Black and white photo of actress Jayne Mansfield leaning out of the window of a military plane wearing flight helmet for promotional photo

Jayne Mansfield in a U.S. Air Force helicopter in Rotterdam, the Netherlands, 1957. | Daan Noske / Anefo / Creative Commons

On June 29, 1967, a Hollywood bombshell and two others were killed in a grisly crash while driving between Biloxi and New Orleans when the car they were riding in hit the back of a slower-moving truck, the driver’s vision impaired by a cloud of pesticide sprayed from a city vehicle. A sex symbol who owned her star power, Mansfield was only 34 at the time of her death. The crash and its widely publicized aftermath led to a call for changes in the design of big rigs to prevent other crashes from having similarly fatal results.

After Mansfield’s death, media photos showed the crumpled Buick Electra with its top practically sheared off by the underside of the truck, with an object that could be interpreted as a blonde head amidst the wreckage. Although, contrary to popular rumors, Mansfield was not in fact ‘decapitated’ in the crash, the actress died from massive skull fractures sustained as the car slid under the much larger truck. The two other adults, college student Ron Harrison and Mansfield’s lawyer, Samuel S. Brody, also seated in the front seat of the car, and Mansfield’s dog, died as well. Mansfield’s three young children, including Mariska Hargitay, who were all seated in the backseat, survived the crash.

The horrifying aftermath highlighted the danger of large trucks and trailers to other vehicles on the road. At the time, there was a federal requirement in place for rear guards, but the rule was loosely enforced and there were no standards for strength or effectiveness. After the National Highway Traffic Safety Administration (NHTSA) was established in 1970, the agency recommended the installation of rear underride guards—or, as they later became known in the United States, ‘Mansfield bars’—on large trucks. The NHTSA withdrew its proposal to mandate underride guards under pressure from the trucking industry and newly elected President Reagan. The requirement for rear guards was finally implemented in 1998.

Today, underride guards are still not mandatory on the sides of trucks and trailers, and road safety advocates continue to urge regulators to strengthen safety measures to protect people in smaller cars. The NHTSA estimates that over 400 people died in underride crashes in 2021, while other experts believe the number to be higher. According to a recent article by Kea Wilson, the NHTSA data vastly underestimates the number of deaths caused by car passengers being trapped under trucks and excludes pedestrian, cyclist, and motorcyclist deaths, estimated at over 100 deaths per year. Wilson’s article also points out that few states record underride events on crash reports, making the issue harder to quantify.

View from back of white tractor trailer on road with rear underride  guards
Rear underride guards are now mandatory on tractor trailers in the Untied States. Image Credit: Kirill Gorlov | Adobe Stock

Jayne Mansfield’s death wasn’t the only celebrity tragedy to draw attention to road safety reforms. TE Lawrence, the legendary namesake of the film Lawrence of Arabia, died of injuries sustained in a motorcycle crash in 1935. His death prompted one of his doctors, neurosurgeon Hugh Cairns, to start advocating for crash helmets, eventually leading the British Army to require its members to wear helmets starting in 1941. The doctor continued to research the effects of crash helmets, eventually leading to more widespread adoption of helmet wearing and regulations.


Diana Ionescu

Diana is a writer and urbanist passionate about public space, historical memory, and transportation equity. Prior to joining Planetizen, she started and managed a farmers' market and worked as a transportation planner in the bike share industry. She is Planetizen's editor as of January 2022.

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