Missing Billings Woman Found Dead in Big Horn County, Homicide Probe

Billings police have escalated the search for Shawna Katherine Grove into a homicide investigation after detectives traced a vehicle connected to her disappearance to Big Horn County and found her dead inside. Grove, who was also known as Shawna Katherine Hart, was 35.

Officers first responded at about 9:20 a.m. on April 24, 2026, to a missing-person report involving Grove. The Montana Department of Justice lists her last contact as April 23, 2026, and records identify Billings police as the investigating agency. Reporting also says Grove was last seen getting into a blue Chevy Traverse, a detail now central to reconstructing her final movements.

Investigators have identified Tanner Grove, 32, as the vehicle’s owner and a suspect in her disappearance, according to Billings police and Montana Department of Justice records. He was arrested on Friday on unrelated charges, including felony assault with a weapon. Court-record reporting says a March 29, 2026 confrontation led to those felony assault charges, and a no-contact order was already in place by October 21, 2025.

Authorities have not publicly released a cause of death, and no homicide charges had been filed publicly in connection with Grove’s death. That leaves the key questions where true-crime cases often turn: how she died, who else may be involved, and what sequence of events carried the case from a missing-person report in Billings to a death investigation in Big Horn County.

The case has hit especially hard because friends and family described Hart as a mother of six. Domestic-violence advocate Lily Aimone said the death reflects wider failures in the system: “We ask for help. We ask for protection orders. It’s not enough.” Kelsey Krueger said she had text messages showing Hart trying for years to leave the relationship, while Deb Switzer remembered Hart’s children and grandbaby as the center of her life.

The public response has already reached City Hall. The Billings City Council chamber was packed Monday night, and council members agreed to continue discussion on preventing domestic violence after emotional testimony from Hart’s son and niece. Councilman Scott Aspenlieder said he wants budget support for better training for staff and officers, while advocates pressed for faster intervention before another missing-person alert becomes a homicide case.