Christopher Matthews, 33, died in January of last year after Ronald Newman punched him. Matthews' head struck the pavement -- he suffered a serious brain injury -- and died a few days later.
Matthews was escorting Newman's wife to her car outside a restaurant when Newman confronted him. He believed the two were having an affair, but there was never any evidence of that.
Newman was on trial for aggravated assault, but on Monday afternoon the jury found him guilty of the lesser charge of misdemeanor assault. Newman now faces up to one year in jail and a fine up to $4,000.