A sheriff’s deputy in South Carolina, who was 29 years old and a Lake County native, died in the line of duty during a dive training session, as officials say she “exemplified commitment and service.”
The Lexington County, South Carolina Sheriff’s Department said Master Deputy Jillian Olson, 29, died in the line of duty on July 30.
Olson was a member of the sheriff’s department’s dive team and died during an underwater training session on Lake Murray, west of Columbia, South Carolina.
Olson, who was 29, began her career as a Lexington County deputy in 2021.
She transferred to a warrant deputy position after more than a year as a patrol deputy.
Olson was promoted to Master Deputy in the Warrant Division in 2025. She had been a member of the LCSD Dive Team since 2024.
“Our hearts are broken by the loss of a valuable member of the Sheriff’s Department,” Lexington County Sheriff Jay Koon said.
“Jillian exemplified commitment and service. She faithfully carried out her duties and selflessly worked to make those around her better,” Koon said.
The Lexington County Sheriff’s Foundation named Olson the outstanding judicial services deputy of the year at its annual awards banquet last spring, Koon said.
“The foundation recognized Jillian for showing exceptional initiative and leadership by, on her own time, developing reference guides and document templates for use by judicial services deputies,” the sheriff said.
“The tools Jillian developed improved deputy training and operational workflow,” he added.
Olson, a resident of Lexington, South Carolina, received the sheriff’s department’s tactical operations support award in 2023.
She was scheduled to receive the department’s five-year honorable service award this month.
Olson is an Illinois native and was raised in Buffalo Grove and Northbrook where her “adventurous spirit, determination, and love for family first took root,” her obituary said.
She graduated from Stevenson High School in Lincolnshire in 2015. The Alumni Association said they were “saddened to share” news of her death.
“From an early age, Jillian dreamed of moving south and serving in law enforcement.” She attended Western Illinois University where she obtained her Bachelor of Science in Law Enforcement and Justice Administration with minors in Political Science and Women’s Studies in 2019.
She later obtained her Master of Science in College Student Personnel Services in 2021.
Olson followed her dreams of moving south and made Lexington, South Carolina, her home in 2021, and was a “loving dog mom” to three dogs.
“Jillian’s dedication to her community and department is well-documented with awards and recognitions,” Koon said. “She’ll be most remembered for what she did with no fanfare. Her decision to join our dive team is just one example of her going above and beyond.”
Olson “embraced life wholeheartedly” and enjoyed spending time on the lake paddleboarding, floating in the water and diving, her obituary said.
“She had recently celebrated her 100th dive, a milestone reflecting her adventurous spirit and love of exploring the underwater world. She was endlessly curious and determined,” her family said in the obituary.
“Jillian was known for her quick wit, infectious laugh, colorful vocabulary, and genuine honesty. She had a remarkable way of making people feel welcome and important. She was fiercely loyal, deeply compassionate, and always ready to help family, friends, coworkers, and anyone in need,” her obituary said.
The South Carolina Department of Natural Resources is leading the investigation into Olson’s death with assistance from the South Carolina Law Enforcement Division.
The Lexington County Coroner’s Office is conducting its own investigation to determine Olson’s cause and manner of death.
“I am grateful to DNR, SLED and our county coroner for the sensitive and respectful way they’ve handled everything,” Koon said. “I would also like to express my thanks to the countless public safety agencies that responded without hesitation from across the whole state to help us in our time of need.”
Funeral services were held in Lexington, South Carolina, last week.
Olson leaves behind her parents, three siblings, a nephew, a niece, her grandparents and many friends.
Her father, Jim Olson, is a former Auxiliary Deputy with the Lake County Sheriff’s Office Auxiliary Deputy Unit.
“She will be remembered for her courage, humor, loyalty, adventurous spirit, and the extraordinary way she made every person in her life feel seen, valued, and loved,” her obituary said.