In March 2020, a family on the Northern Cheyenne reservation in Lamedier Montana got shocking news about their loved one.

Christy wouldn't die.

My daughter came and notified me that Christy was run over.

And I said, it should be okay. And she's like, no, she died. I was like, what?

Missing justice from CBS News takes you inside what really happened that night,

and the federal investigation that followed.

Listen to Missing Justice from CBS News on Amazon Music or wherever you get your podcasts.

She was afraid for her life. I mean, I was constantly afraid for her life.

I messaged her every morning to see if she was still alive.

On the night of the shooting, my phone rang. And it was little after two in the morning.

And it's Nikki. She sounded so scared.

I'm so sorry. I'm so sorry.

Nikki, Audimonda, better than anybody else in this world knew how dangerous he was at that moment.

She had been asking him sort of throughout the night, you know, just let us leave, just let me leave with the kids.

What was he saying? He told me I'm not going anywhere. I'm not leaving.

He pulled a gun out of the couch and said he would kill her. I need him.

And when she did that, the gun fell to the floor.

I picked it up and he said, what did he do to it?

Nikki didn't attempt to evade the police and didn't hide the fact that she shot him.

He's playing on the couch. He's playing there.

Nikki is the most gentle, loving friend we've ever had.

Everything she does is for her kids.

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