A police officer and his estranged wife have a fight in their bedroom.

A shotgun goes off.

He says it was suicide.

Investigators said it was murder.

There's only two people that know, and one can't speak with us.

It took ballistics, a last will, and the physics of a shot cup pedal to tell what really

happened in the bedroom that day.

In the desolate beauty of northwest New Mexico,

the city of Farmington is one of the few green spots.

The streets are generally quiet.

Traffic problems are usually handled by police on motorcycles.

Paul Dunn used to be one of those officers.

I loved my job. I always used to say there was only two things I was good at. I was being a traffic cop and being a dad.

And I enjoyed most all the simplicity of being a motor cop because everything you do

an accident investigation accident reconstruction it's just math cliff olem worked alongside paul done

he was a good motor officer good police officer took his job, you know, real serious.

Paul was married to Monica Sanchez Don, and together the couple had two children.

She was singularly of the most beautiful woman I'd ever seen in my life.

But after several years of marriage, there were problems.

Monica discovered Paul was having an affair with another woman, and the couple separated.

Early on the morning of April 4, 1994, Cliff Olin was on duty and heard a police radio call about a shooting at Paul and Monica's house.

I saw Paul performing CPR on Monica, and he was just covered in blood.

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