ThinBlueNews Memorial Wall

Special Agent Quincy Kjerstad

South Dakota Division of Criminal Investigation
End of Watch: Monday, September 14, 2026

PIERRE, S.D. — ThinBlueNews remembers Special Agent Quincy Kjerstad of the South Dakota Division of Criminal Investigation, whose End of Watch was Monday, September 14, 2026. He was 38.

The Officer Down Memorial Page added Kjerstad to its recent line-of-duty death roster and currently classifies the cause as a heart attack. ODMP records that he suffered the medical emergency after completing a physical-fitness training test in Rapid City on September 11 and died three days later.

Remembered by South Dakota DCI

In a September 16 official release, the South Dakota Attorney General’s Office and DCI said Kjerstad suffered a medical event while on duty on September 11 and passed away September 14. The release described him as a valued colleague, public servant and investigator whose courage and commitment left a lasting mark.

Dakota News Now independently reported the agency announcement and the West River Major Crimes Unit assignment.

Service to South Dakota

The Attorney General’s Office said Kjerstad began state service in June 2017 as an assistant attorney general, working in the Appellate and Civil Litigation divisions. He was appointed a DCI special agent in March 2023 and served with the West River Major Crimes Unit, investigating major felony offenses across 13 western South Dakota counties.

DCI Director Chad Mosteller remembered Kjerstad as composed, thoughtful and steady, and as a mentor and trusted colleague. ThinBlueNews extends condolences to his family, friends, colleagues and the communities he served.

Current classification

The Attorney General’s release described an on-duty medical event. ODMP’s current memorial provides the more specific heart-attack and physical-fitness-test classification. ThinBlueNews attributes those details to ODMP and will update this stable memorial if the agency, investigating authorities or ODMP publish materially different verified findings.

Special Agent Quincy Kjerstad is remembered for dedicated service, steady leadership and commitment to the people of South Dakota.

End of Watch

Special Agent Quincy Kjerstad
South Dakota Division of Criminal Investigation
South Dakota
End of Watch: Monday, September 14, 2026
Age: 38
South Dakota Attorney General’s Office service: June 2017–September 2026
DCI service: March 2023–September 2026
Assignment: West River Major Crimes Unit
Cause listed by ODMP: Heart attack

Sources and visual note

Visual note: The image is a contextual photograph of the South Dakota State Capitol by Jake DeGroot, obtained through Wikimedia Commons and licensed under CC BY-SA 3.0. ThinBlueNews cropped the photograph, added a memorial treatment and labels, and releases this adapted memorial image under CC BY-SA 3.0. It does not depict Agent Kjerstad or the medical event. Use does not imply endorsement by the photographer, Wikimedia Commons, Creative Commons, the South Dakota Attorney General’s Office or DCI.

ThinBlueNews will update this stable memorial if authorities release materially new verified information. Corrections may be submitted through our corrections and editorial standards page.