The Lexington County Sheriff’s Department is mourning the loss of Master Deputy Jillian Olson, who died July 30, 2026, during an underwater training exercise on Lake Murray. She was 29.

Olson was participating in a training session as a member of the department’s dive team when the incident occurred. The South Carolina Department of Natural Resources is leading the investigation into her death with assistance from the South Carolina Law Enforcement Division. The Lexington County Coroner’s Office is conducting a separate investigation to determine her cause and manner of death.

“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.”

Olson joined the Lexington County Sheriff’s Department in 2021 after earning both bachelor’s and master’s degrees from Western Illinois University. A native of Illinois, she graduated in 2019 with a bachelor’s degree in law enforcement and justice administration before completing a master’s degree in student personnel services in 2021.

She began her career as a patrol deputy before transferring to the Warrant Division after more than a year on patrol. In 2025, she was promoted to master deputy, continuing her service in the division while taking on additional responsibilities throughout the department.

In 2024, Olson became a member of the department’s dive team, volunteering for one of the agency’s most specialized assignments. Dive team members respond to incidents requiring underwater search, recovery, and rescue operations while maintaining proficiency through ongoing training in challenging and often hazardous conditions.

Throughout her career, Olson earned recognition for both her operational contributions and her commitment to improving the department.

In 2023, she received the Sheriff’s Department’s Tactical Operations Support Award. Last spring, the Lexington County Sheriff’s Foundation named her the Outstanding Judicial Services Deputy of the Year after recognizing her initiative in developing reference guides and document templates for judicial services deputies during her own time.

According to Sheriff Koon, the resources Olson created strengthened deputy training and improved operational workflow throughout the division.

“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,” Koon said. “The tools Jillian developed improved deputy training and operational workflow.”

Olson was also scheduled to receive the department’s Five-Year Honorable Service Award next month, marking another milestone in a career defined by professionalism, dedication, and a willingness to serve wherever she was needed.

Sheriff Koon said that while Olson’s accomplishments were reflected through awards and promotions, those who served alongside her will remember the quiet dedication she brought to her work every day.

“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.”

Following the training incident, public safety agencies from across South Carolina responded to assist Lexington County personnel. Sheriff Koon expressed his appreciation for the support provided by responding agencies, as well as the professionalism shown by investigators from DNR, SLED, and the Lexington County Coroner’s Office during the initial response.

“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.”

Master Deputy Olson’s death is a profound loss for the Lexington County Sheriff’s Department and the law enforcement community across South Carolina. Her career reflected a commitment to public service that extended beyond her assigned duties through mentorship, innovation, specialized training, and a willingness to support those around her.

The South Carolina Fraternal Order of Police extends its deepest condolences to the family of Master Deputy Jillian Olson, Sheriff Jay Koon, the men and women of the Lexington County Sheriff’s Department, and all who had the privilege of serving alongside her. We join the law enforcement community in honoring her service, remembering her dedication, and keeping all those affected by this loss in our thoughts during the difficult days ahead.