(NBC News) — Friday on “Dateline,” a family begins a relentless pursuit of justice after the death of attorney Susan Winters is ruled a suicide.

Here is a preview of correspondent Josh Mankiewicz’s report:

It was a tragic loss — one that might have united a family in grief — instead, it tore them apart in anger.

AVIS WINTERS: It was just very cold and hostile.

CHRIS WINTERS: The lines were drawn, and he wasn’t backin’ off.

An open and shut case became a puzzle with a lot of missing pieces.

TONY SGRO: There’s a lot of trying to put a square peg in a round hole.

KATE BRIQUELET: There’s a lot of clues in this story, but no easy answers. It seems like it just doesn’t add up.

A family pushed back against the criminal justice system.

JOSH MANKIEWICZ: You knew that was gonna be the most uphill of uphill battles?

JULIE WINTERS: Yes.

CHRIS WINTERS: All we want to know is the truth.

And they refused to give up.

JOSH MANKIEWICZ: “You’re both grieving parents, and you need to let it go,” how many times did you hear that, and from how many people?

DANNY WINTERS: We heard it from everybody that we talked to.

AVIS WINTERS: But we’re stubborn people.

Watch an all-new “Dateline: A Cool Desert Morning,” Friday at 9 p.m. on NBC4.