On June 28, Deputy Serrato responded to a separate multi-vehicle crash in the northbound lanes of I-45 caused by a man, identified as Ashton Jammer, according to MCSO. Jammer was arrested and charged with DWI, officials said.
While assisting with the crash, Serrato was hit and killed by a heavy-duty Freightliner truck.
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The lawsuit, filed by the deputy's parents, alleged that the Freightliner's driver, 20-year-old Ian Perez, fell asleep at the wheel while traveling at 65 miles per hour and didn't see the emergency lights or slow down to prevent hitting Serrato.
The Department of Public Safety arrested Perez and later charged him with passing certain vehicles in violation of bodily injury as a result of failing to slow down or move over while passing emergency vehicles, officials said. A magistrate set his bond at $10,000.
The lawsuit says that the commercial truck is linked to North Houston Pole Line, Quanta Services, and Quanta Telecommunication Solutions. It was allegedly owned by one of the several corporations through Element Fleet Corporation, the suit said.
Serrato's family claims in the lawsuit that corporate organizations failed to exercise reasonable care in hiring Perez. The lawsuit says that the companies failed to adequately review his driving history, evaluate his fitness for work, and ensure he was qualified to drive the commercial vehicle.
"The lawsuit alleges that this tragedy occurred because a commercial driver fell asleep at highway speed and failed to heed the emergency lights ahead. We are committed to seeking answers, accountability, and justice for Erika's family," said Brant J. Stogner, law parnter with Abraham Watkins.
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Serrato began her career with the sheriff's office as a detention officer at 18, before becoming a commissioned deputy earlier in 2026.