You are a Lodi police officer on patrol in an upscale residential section on the west end of our city.

It is a quiet summer night, and you are cruising the side streets with your headlamps off, looking for auto thieves and burglars.

Suddenly, your radio comes alive with a report of a family disturbance, heard by neighbors at a house only blocks away from your present location. You are on the scene in seconds, though your backup calls in that she is still miles away.

The report is that a "male-female argument" is in progress in the backyard, and as you exit your patrol car, you hear raised voices coming from behind the house. You walk quickly to one side of the house in search of a gate and you find one; fortunately, it's unlocked. You could go in. But your training is to hold back, to wait and listen, to try to get an idea of what is going on while your backup is on the way. Then when you have the help you need to cover each other, and (if needed) to make an arrest in a safe manner, you would walk back and reveal your presence.

The best laid plans do go astray, however, and so does yours as you hear the female voice begin screaming, "No, please! Please don't! I'm sorry!" You would like to have your partner with you, but the sound of that voice tells you that someone is in real trouble. You head down the side of the house and emerge into the backyard. There, you find a strange and frightening sight.

A naked man stands above a bubbling hot tub. An obviously terrified woman sits in the water, looking up at him, pushing herself against the opposite side of the small pool. He holds a black box connected to a length of black wire that continues out of sight. You vaguely recognize it as some type of electrical transformer, such as the type used with outdoor lighting. You start toward him, but the man sees you as soon as you turn the corner. He shouts drunkenly, "I'll throw it in! Back off!" He holds the box out over the water, and you stop. The woman screams repeatedly and starts to rise from the pool. She slips and falls back into the water.

The two people are about 25 feet away from you. The man starts screaming at the woman, who is crying hysterically. You are shouting at the man, ordering him away from the pool, while you draw your pistol. He seems not to hear you, as he lets the hand holding the box fall to his side and points at the woman with the other. Just then, your backup rounds the corner. The man looks up, sees her and begins to raise the box again. You have your pistol sighted in on the man's chest. You feel your heart pounding.

What do you do?