BILLINGS, Mont.- An Army veteran has been found guilty of slashing the throat of a former Marine during a drunken argument over which branch of the military was better.

Jurors convicted 63-year-old William Earl Cunningham of deliberate homicide Friday in the August 2014 death of 40-year-old Nathan Horn in Laurel.

Prosecutors said Cunningham told responding deputies: "I cut him, he's dead."

Deputy Yellowstone County Attorney Christopher Morris told jurors during closing arguments Friday that the facts do not support Cunningham's story that the two men were standing up when Horn's throat was cut.

Public defender Gregory Paskell urged jurors to look at the whole picture, which involved two nights of Horn drinking with, antagonizing and threatening Cunningham.

Cunningham argued he acted in self-defense.