Mansfield bars got their name from legendary actress Jayne Mansfield, who was tragically killed in an incident in which the car she was in slammed into the rear of the truck in front of it.


These sorts of collisions are particularly not for the squeamish, as the Snopes description of Mansfield’s death details (WARNING: feel totally free to scroll past this bit, trust me on this one):

The precise nature of the injuries inflicted in this accident would not usually bear thinking about, but rumors about the death of one of the passengers was turned into the stuff of contemporary lore when it became “common knowledge” that Jayne Mansfield had been decapitated. It is because this belief is as widespread as it is that this topic merits study, and it is due to the nature of the rumor that the discussion needs to be as detailed as it does.

Although Mansfield’s actual mode of death was gruesome, she was not beheaded. According to the police report on the accident, “the upper portion of this white female’s head was severed.” Her death certificate notes a “crushed skull with avulsion (forcible separation or detachment) of cranium and brain.” One thinks of a beheading as the neck’s being sliced through, causing the head to be separated from the body, but that is clearly not what happened here. Scalping is perhaps a closer description of Mansfield’s fate, but even that word does not accurately reflect the cranial trauma she suffered, because scalping victims at least retain an intact skull. The Angel of Death did not afford Mansfield this luxury: Her skull was cracked or sliced open, and a sizeable piece of it was carried away.


Even though Mansfield died in 1967, and the federal government mandated the bars that bear her name shortly after, most of them didn’t actually do much of anything, as the IIHS pointed out three years ago:

And all of this wasn’t just for some gruesome tales or chilling video, as the IIHS points out:

In 2015, 427 of the 2,646 passenger vehicle occupants killed in large truck crashes died when the fronts of their vehicles struck the back of trucks. That is up 39 percent from 2011 when 260 of the 2,241 passenger vehicle occupants killed in large truck crashes died in impacts with the rear of a large truck. Gaps in federal crash data make it difficult to pinpoint exactly how many of these crashes involve underride.

In a 2012 IIHS study of fatal crashes between large trucks and passenger vehicles, an estimated 15 percent involved the rear of the truck. An IIHS analysis of a smaller sample of fatal crashes found that 82 percent involving the rear of the truck produced underride.


But once the bars started getting a little bit of publicity from the IIHS, it looks like their makers have finally gotten around to fixing some of the problem.

Now we just need similar equipment for the sides of semi-trailers.