An arrest was made Wednesday morning in the 2008 homicide of Susan Casey. Casey was reported missing in April 2008 and her body was later recovered from the Yellowstone River near Fallon.
Walter Larson was arrested in Phoenix, Arizona, at 6:10 a.m. by a Montana Division of Criminal Investigation agent and a Glendive Police Department officer, with the assistance of the Phoenix Police Department. Larson, Casey’s ex-husband, is jailed in Phoenix pending extradition to Montana on charges of deliberate homicide and tampering with evidence. He is being held on $500,000 bail.
The investigation into Casey’s homicide was a joint effort involving the Dawson County Sheriff’s Office, the Glendive Police Department and both the Division of Criminal Investigation and the Prosecution Services Bureau within the Montana Department of Justice.
Charging documents in the case were jointly filed by Dawson County Attorney Olivia Norlin-Rieger and Assistant Attorney General Brant Light, Chief of Prosecution Services with the Montana Department of Justice. The state cited 49 witnesses for the case.
The documents say that Casey's plight first came to light when her children called a relative after they woke on the morning of April 12, 2008 and found that she had not come home. The relatives then went to the police.
The documents also reflect Casey had a complicated personal life. She divorced Walter Larson in the 1990s, later married Ted Casey, and at the time of her disappearance was separated from Mr. Casey and seeing a new person. During an interview shortly after her disappearance Larson told investigators that he and Casey were in the process of reconciling and were planning to move to South Dakota together with their children in the fall of 2008.
Court documents also say that Larson created a fake, female online persona and contacted the new person via email challenging his relationship with Casey and he contacted Ted Casey by telephone regarding the third man.
The documents also detail Larson's journey to and from Glendive on April 11 and 12, 2008 and include bank camera footage of Susan arriving home and places Larson at that location before and after Susan was dropped off.
Charging documents quote Larson, who divorced Casey in the 1990's, as saying he was hurt by the divorce and a 1998 restraining order put on him by Casey was a result of his lashing out from that hurt. During that episode he stole identification from Casey and her husband and came to Glendive carrying a 12-gauge shotgun. During that episode he was scared off by a vehicle he believed to be law enforcement. About that episode he said “I was hurt and I was lashing out. I didn't understand how to deal with things very well.” Also during questioning he was asked if he knew about Casey's new relationship and he similarly said that the situation also “Hurt. Hurt more than anger.”
If convicted Larson faces 10 to 100 years prison for deliberate homicide and up to 10 years and/or a $50,000 fine for tampering with evidence.