Perham teen faces adult charges in Frazee home invasion murder case

A 17-year-old Perham teen now faces adult felony charges in the Frazee home invasion killing of Bryson Andrew May, adding another legal layer to a case that has moved across small towns in Becker County and Otter Tail County.

Cash Christofer Mathieu appeared in Becker County District Court on May 4, 2026, and waived juvenile certification proceedings, accepting that an adult court file would be created. The latest filing identifies Mathieu as the driver in the Dec. 20, 2025, incident in Frazee, where prosecutors say he is charged with first-degree aggravated robbery and aiding an offender to avoid arrest.

Under Minnesota law, first-degree aggravated robbery is punishable by up to 20 years in prison and a fine of up to $35,000. Juvenile certification law allows a child age 14 or older to be moved into adult court when the alleged conduct would be a felony if committed by an adult, a step that sharply raises the stakes and expands the public record as the case advances.

The case began in the early morning hours of Dec. 20, 2025, when the Becker County Sheriff’s Office was called at 2:38 a.m. to a home on West Ash Avenue, also listed as 701 W. Ash Avenue, in Frazee after a 911 call reported that someone had fired a gun. Deputies found that a shooting had occurred. May, 19, of Frazee, was taken to Essentia Health St. Mary’s-Detroit Lakes and later pronounced dead.

Authorities said four people fled the scene in a black SUV. Law enforcement later located the vehicle about 11 miles southeast in Perham, where an Otter Tail County deputy helped with the arrests. Earlier court action had already named 21-year-old Arthur Deshun Campbell of Frazee in a second-degree murder charge and identified 16-year-old Kayne Nobel Mackner of Detroit Lakes as a juvenile co-defendant, leaving Mathieu as the third suspect now brought into the adult case.

May was born Sept. 4, 2006, and an obituary described him as a member of the Bear Clan, the son of EmmyLou Johnson and Tony May Jr. Family members said he was selfless and always helped others, a reminder of the personal loss behind a case that has left both Frazee and Perham watching the legal process closely as prosecutors sort out each alleged role in the killing.