Understanding the crime of homicide

Dear PAO,

My husband and Alfred were crewmembers of a cargo vessel. Unfortunately, they had a heated argument on board the ship where they were working. As a result, my husband drew a knife and threatened to kill Alfred. Alfred, believing that he was in great danger, threw himself into the water. Sadly, Alfred died. Now, my husband is in jail and charged with homicide. I spoke with my husband, and he said that he only threatened Alfred with a knife to intimidate him. There was never an intention on his part to kill his workmate. Is the charge against my husband correct, considering that he never touched Alfred and had no intention to kill him?