(NBC News) – Tonight on “Dateline,” when Kathleen Schroll makes a phone call that names her killer right before her death, it leads to the arrest of a father for murder. But two trials and 12 years later, authorities begin to wonder if he was the victim, not the villain.

Here’s a preview of Natalie Morales’s report: 

The two teenagers who’d been with their dad in the van were down at the station in interrogation rooms. Melody was 14.

MELODY BITZER: I. I was just very, very confused and afraid and on the verge of tears. I had zero insight as to what could possibly be happening.

NATALIE MORALES: And, and sitting there for how, how long bef–

MELODY BITZER: Hours

Ben, who was 17 then, says he was scared too.

BEN COONES: Eventually two officers came in and started questioning me about where my dad was the night before. What he was wearing what he was doing. What I was doing the night before. And I couldn’t really give ’em too much information, ’cause I hadn’t paid that much attention Not to mention I was already internally panicking and kind of shutting down to try and deal with what had– was goin’ on. I was handcuffed to a chair in a interrogation room by myself for a solid three hours.

It was afternoon when Ben and Melody were returned home.

MARIAH MINKS: Two cop cars pulled up. And they got out. Melody was a ball of tears

DEE COONES: I didn’t know what, still didn’t know what was going on.

Dee says she was completely in the dark until a detective finally laid it all out. Her husband had been arrested for the murders of Kathleen and Carl Schroll.

DEE COONES: they came back with a warrant. And the phrase they used was, “We’re gonna– we gotta toss this house.” And believe me, they tossed the house.

Investigators confiscated computers and looked for guns and ammunition. They also searched Pete’s van for gunshot residue and blood.

NATALIE MORALES: Was there ever a thought in your mind?

DEE COONES: No.

NATALIE MORALES: Maybe?

DEE COONES: No.

NATALIE MORALES: Never.

DEE COONES: Never.

Never, because the family says they knew something police did not.

Watch “Dateline” Friday’s “The Phone Call” tonight on NBC4 at 9 p.m.

About “Dateline”

“Dateline NBC” is the longest-running series in NBC primetime history and is in its 30th season. Dateline is anchored by Lester Holt and features correspondents Andrea Canning, Josh Mankiewicz, Natalie Morales, Keith Morrison and Dennis Murphy.

Dateline is the #1 Friday newsmagazine and reaches more than 17 million people every week through its broadcast, and millions more through its social media platforms and podcasts.

The stories range from compelling mysteries to powerful documentaries and in-depth investigations. When major news breaks, they go to the scene, putting the pieces together to bring the viewer the full picture. And in every story they tell, they help the real people who lived the events share their journeys with the viewer.

This past season, Dateline debuted two new podcasts, “Mommy Doomsday” and “Killer Role,” hosted by correspondent Keith Morrison.

In February, NBC also greenlit a straight-to-series inspired by the story featured in the Dateline podcast series, “The Thing About Pam.” Two-time Oscar-winning actress Renee Zellweger will star and executive produce the series, in collaboration with Blumhouse Television, NBC News Studios and Zellweger’s Big Picture Co.