CHARLESTOWN — Christa Hammack had her first-born daughter, Erin Alexander, in 1995 when she was a senior in high school.

Though she had roots in the area — she attended St. Mary's Catholic School in New Albany and Assumption High School in Louisville — Alexander's heart was always in Texas, where her family had lived for a stint when she was a child.

Because of that longing, she moved to Austin to attend the University of Texas before ultimately landing a job at her father's winery in nearby Fredericksburg.

Despite the distance, Alexander always made it a point to stay in touch with her family in Indiana.

"We would literally call or text every day," Hammack said. "There was always some sort of contact. Even when she was out of the country, she would email or send something small and short. She couldn't wait to see her sister. We were preparing her little sister to fly by herself to meet her sister in Dallas to go to a Harry Styles concert. It was time for her to be the big sister away from mom."

On May 4, 2018, the day of the Kentucky Oaks, Alexander became noticeably unresponsive.

"Up until that day, Erin was helping me find my hat and pick shoes and dresses," Hammack said. "That morning, she had sent me a text and told me she loved me and that I looked good. I told her that I wish she was here. That would be our last conversation."

While driving to work that day, Alexander and friend Jordan Hensley were killed when their car was involved in an underride crash with a semi truck. An underride crash is when a vehicle goes underneath a semi trailer.

Hensley was driving the vehicle in the far-right lane of the four-lane highway, which had no median. The truck crossed from the opposite far-right lane before colliding with the vehicle in front of them.

"When he tried to correct, the truck couldn't handle it and the trailer portion went sideways, almost perpendicular," Hammack said. "It was covering all the lanes to where the girls had nowhere to go except underneath, and they were drug 100 feet. The girls died instantly."

At first, Hammack only knew that Alexander had died in a car crash. When she learned the details, Hammack said she entered a three-day period of which she barely has any memory.

"As you can imagine, my world turned upside down," Hammack said. "At that point when I found out what happened with the semi, it took me three days to come to. That's when I went to that dark place. My worst imagination had come true."

FIGHTING TO FIND LIGHT

From that darkness, Hammack emerged seeking answers. She knew nothing was bringing Alexander back, but she wanted to find out what could have been done to prevent such an accident.

"Over time, as I learned about the accident and what underrides were, I started to educate myself," Hammack said. "No expert came to me. I just started to think about what underrides were and if there was something in place to where the girls could've survived by deflecting the accident."

Enter the Stop Underrides group, which has advocated for guards on the sides and fronts of semi trucks and trailers since its formation. Through her own research and the work of the advocacy group, Hammack learned that there is much more to the issue of underride crashes than what's reported.

Efforts to prevent smaller vehicles from going under trailers is nothing new. A patent for one design of side guards has existed since 1915. Rear guards, often referred to as Mansfield bars, have been standard on trailers since the movie star Jayne Mansfield and two others died when their vehicle was involved in an underride crash in 1967.

But since then, progress has seemingly stalled. A 2019 report from the U.S. Government Accountability Office noted that rear guard inspections are not required. Despite recommendations from the National Transportation Safety Board, front guards are still not mandatory. Additionally, the report recommended research into side underride guards be done, since data is notoriously unreliable due to underreporting.

Perhaps most frustrating is the fact that trailer manufacturers in Indiana already have a patent on side guards similar to those currently used in parts of Europe and Asia. Since there is no mandate to add the bars to trucks and trailers, companies are choosing not to do so. This comes despite reports estimating that such bars would only cost 62 cents per day when spread out over a trailer's usual 15-year lifespan.

"To me, that creates the urgency to get the legislation to go," Hammack said. "I do believe that both sides of Congress want clarification on this. I feel like people needed to be aware that lives can be saved, just like with seatbelts and airbags. My focus is death prevention, not crash avoidance. There's computer error and there's man error. My look at it is there's weather and traffic. You just can't avoid certain situations."

MORE THAN A PASSIONATE MOM

Equipped with knowledge and a purpose, Hammack has spent the last year fighting to prevent crashes like those that took Alexander's life.

Hammack has attended tests where vehicles were crashed into trucks and trailers equipped with side guards, like AngelWing and a different design that uses webbing as a safety skirt.

"It showed that at 35 miles per hour, there was no compartment intrusion, which is 99% cause of the death," Hammack said.

Hammack also travels to Washington, D.C., when her schedule allows it. Most recently, she attended the House Subcommittee on Highways and Transit's hearing, Under Pressure: the State of Trucking in America, on June 12.

While on such trips, she has spoken with numerous members of Congress, including those from her home state. She's also had meetings with leaders from the trucking industry, like the American Trucking Associations. The productivity of these meetings, she said, has been hit-and-miss.

"I've not gotten a lot of movement from that," Hammack said.

Though conversations have been cordial, Hammack said she still gets the feeling that some aren't taking her fight as seriously as they should.

"One of my biggest frustrations is that people think I'm coming from the side of a passionate mother who lost her daughter," Hammack said. "That's very true, but that's what drives me to find out truths about underrides. It incorporates discussions and research. My biggest interest is that Europe and Asia have had [guards] for 15 years. It's been proven. They keep getting better, and they're proving that. There's a lot to be done."

THE BUTTERFLY EFFECT

Over the course of the past 50 years, there have been several recommendations made to make semi trucks and trailers safer for surrounding vehicles, including failed legislation.

Despite the difficulties, Hammack is hopeful that current lawmakers will recognize the need to get laws on the books. Without such a mandate, trucking companies and manufacturers have no motivation to equip safety bars.

In March 2019, each chamber of Congress introduced identical bills with a short title of the Stop Underrides Act. The legislation would require the installation of underride guards on the sides and fronts of trucks and calls for updates to current standards for rear underride guards.

'It's as simple as needing the mandate," Hammack said. "The more discussion we have and the more movement, the more likely it's going to happen."

Her fight for legislation will continue, but Hammack said she is learning to find peace in her personal life.

The butterfly effect is when small changes in cause create significant changes in outcome. Though different than the exact scientific and philosophical definition of the theory, Hammack believes that her one voice, in addition to the many others by her side, can have a huge effect in changing the current state of highway safety.

Coincidentally, it's through butterflies that Hammack is also finding her personal peace.

"There's a strange butterfly connection," Hammack said. "Since she was a baby, [Alexander] had a caterpillar. Days after the accident, there were just these occurrences of butterflies that we didn't look for. I built a butterfly garden. Ever since then, I just try to see her face in some of these things. She just was a generally happy person. I miss that. I miss it everyday. Her senior year, she made me this beautiful little box. She didn't have an artistic bone in her body, but she made me this piece of pottery that has a butterfly on it. I found that, and it's given me some peace."