A Florida woman intentionally drove an SUV carrying her boyfriend into the woods after becoming enraged over text messages from another woman, prosecutors told jurors Tuesday. The vehicle was traveling close to 100 mph when she made the sharp turn, they said.
Defense attorney Reid Hart presented a different account in opening statements, suggesting that something inside the SUV triggered the sudden maneuver—an event Leigha Mumby neither expected nor controlled.
Mumby, 25, has pleaded not guilty to vehicular homicide and reckless driving causing serious bodily injury in connection with the death of Daniel Waterman, 22. Waterman initially survived the Feb. 9, 2025, crash but died eight months later.
Assistant State Attorney Melissa Clark told jurors that Mumby and Waterman had left a Super Bowl party shortly before the crash on Interstate 95 in Flagler County, according to proceedings livestreamed by Court TV.
Leigha Mumby sits between her attorney, Reid Hart, and her legal assistant Monday during jury selection for her trial at the Kim C. Hammond Justice Center in Bunnell. (USA TODAY Network via Reuters Connect)
Clark said the SUV’s speed topped 100 mph before the wreck. Data recovered from the vehicle showed it was traveling 94 mph in the final seconds before making an “abrupt, left-hand turn at 45 degrees,” sending it off the interstate and into the surrounding woods.
The prosecutor characterized the maneuver as “a dangerous and reckless” decision.
Waterman suffered a fractured neck and was paralyzed from the neck down, Clark said. He later slipped into a coma and, after regaining consciousness, was unable to breathe without assistance.
Waterman died Oct. 8, 2025, from injuries that were “directly related and caused by this crash,” Clark said. Jurors, however, will not hear Waterman’s own description of what happened—an account he gave detectives before his death.
From his hospital bed, Waterman told investigators that Mumby deliberately swerved off the road after the pair argued about messages from another woman. A judge ruled the statements inadmissible, preventing prosecutors from presenting that account to the jury.
Daniel Waterman died on Oct. 8, 2025, from injuries he suffered in a February car crash. (Heather Waterman via FOX35 Orlando WOFL)
Hart described the case as a “pure and utter tragedy” and asked jurors to consider whether the SUV veered suddenly because of something beyond Mumby’s control.
“The crux of this trial effectively comes down to one steering wheel input, and ultimately one question,” Hart said, according to Court TV’s livestream.
Hart asked jurors to determine whether Mumby intentionally drove off the highway or whether something inside the vehicle occurred that “she did not expect, she did not anticipate, and she did not control.”
He said Mumby tried to avoid the collision but was unable to stop the SUV once it began racing toward the woods.
Leigha Mumby, 24, had charges upgraded to vehicular homicide following Waterman’s death. (Flagler County Sheriff’s Office)
Among Tuesday’s witnesses was Sarah Stappenbeck, Waterman’s cousin and Mumby’s best friend, who hosted the Super Bowl gathering.
Stappenbeck testified that Mumby had announced earlier in the day that she was pregnant. At the same time, Mumby was worried about Waterman’s interactions with other women.
Mumby “expressed concerns of Daniel talking to other girls and said that she wasn’t going to let Daniel cheat on her,” Stappenbeck told jurors.
The couple left before the game ended. About 20 minutes later, Stappenbeck said, Mumby called her in a rage, claiming Waterman was texting another woman and saying she intended to bring him back to the house.
“She’s yelling at me,” Stappenbeck recalled.
Stappenbeck said she did not hear Waterman speaking in the background. She tried to calm Mumby and urged the couple to get home safely and address their disagreement the following day.
“She just said that ‘You’re taking his side,’ and hung up with me,” Stappenbeck testified.
About 20 minutes later, Mumby called again, still angry, and repeated that she was bringing Waterman back, Stappenbeck said.
They never arrived. Instead, Stappenbeck testified, Mumby’s roommate called and told her to go to the hospital because there had been a crash.
The trial is unfolding without Waterman’s account to investigators of what happened inside the SUV.
The portion of I-95 North in Flagler County, Fla., where the crash happened in February 2025. (Google Maps)
Before his death, Waterman told detectives Mumby deliberately caused the wreck after an argument over a text from another woman, according to charging documents previously reported by Court TV.
He said the last thing he remembered was Mumby telling him, “I don’t care what happens, you’ll get what you deserve,” before swerving off the road.
Judge Dawn Nichols ruled those statements could not be introduced at trial. Prosecutors said they wanted jurors to hear Waterman’s account, but acknowledged the rules of evidence prevented them from using it at trial, Court TV previously reported.
“The court is bound by the law and the court is bound by the rules of evidence,” Nichols said when explaining the ruling.
The first day of Mumby’s trial also brought an emotional moment for Waterman’s family. His mother, Heather Waterman, was seen wiping away tears as a photo of her son was shown in court.
Court adjourned for the day following Tuesday’s proceedings.
Mumby was initially arrested in July 2025 on charges of reckless driving causing serious bodily injury and aggravated battery with a deadly weapon.
After Waterman died, prosecutors upgraded her charges to include vehicular homicide. She was booked into the Flagler County Jail and released after posting a $150,000 bond.
Waterman’s mother previously told Syracuse.com that he spent time in a coma before recovering enough to tell investigators what happened.
Waterman’s aunt, Tiffany Waterman, expressed anguish over the exclusion of her nephew’s statements in a Facebook post Monday as jury selection began.
She remembered his efforts to comfort a loved one watching a movie beside him in his hospital bed, smiling at her while trying to conceal his pain.
“That’s who Daniel was. Protective, loving, and sweet,” she wrote. “He had the biggest heart, even in those last moments of life.”
The family previously told News Media through attorney John Hager that they supported the charges filed following Waterman’s death.
“There are no real winners in this situation. It’s a terrible, horrible situation,” Hager said in November 2025, adding that the family believed the charges were “right and just.”
Mackenzie Shirilla makes a statement to the court during her sentencing in the Cuyahoga County Common Pleas Court in Cleveland, Ohio on Aug. 21, 2023. Shirilla was found guilty of four counts of murder and other charges relating to the deaths of her boyfriend, Dominic Russo, and his friend, Davion Flanagan, in July 2022. (Law&Crime livestream)
Mumby gave birth to a baby girl three days after Waterman died, according to WSYR.
“Daniel was an excited, soon-to-be father of a baby girl,” his obituary said. “He wanted nothing more than to come home to her and to the family who loved him so dearly.”
Similar case
The trial comes amid renewed attention to another deadly crash involving a young woman convicted of intentionally driving into a building with her boyfriend inside.
Mackenzie Shirilla is serving two concurrent sentences of 15 years to life for killing her boyfriend, Dominic Russo, 20, and their friend, Davion Flanagan, 19, in a 2022 crash in Strongsville, Ohio, News Media previously reported.
Shirilla’s case became the subject of Netflix’s “The Crash.”
She was convicted in 2023 after prosecutors argued she deliberately drove into a brick building at nearly 100 mph to end her relationship with Russo.
The Ohio Supreme Court recently rejected her request to reconsider its decision, declining to hear her latest appeal. Shirilla has maintained the crash was not intentional.
