Fifth arrest made in homicide of Devon Sinclair Marsman

CITYnews halifax / By Dan Ahlstrand

Halifax Regional Police have arrested a fifth person in connection with the homicide of Devon Sinclair Marsman.

Police say 40-year-old Mark Douglas Robert Doyle was taken into custody at 7:35 a.m. on Thursday. He has been charged with being an accessory after the fact to murder and is scheduled to appear in Halifax Provincial Court Friday.

Marsman was last seen on February 24, 2022, in the Spryfield area. Police declared his death a homicide on September 17, 2024.

Last week, investigators confirmed that remains discovered during the investigation belonged to Marsman.

To date, four others have been charged:

• Treyton Marsman, 26 – Second-degree murder, indignity to human remains, and obstructing justice.
• A unidentified man, 20 (who was a youth at the time) – Accessory after the fact to murder and obstructing justice.
• Emma Maria Meta Casey, 23 – Accessory after the fact to murder, indignity to human remains, and obstructing justice.
• Chelsey Herritt, 26 – Accessory after the fact to murder, indignity to human remains, and obstructing justice.

The police investigation remains ongoing.