By Ginger Allen | Produced By Kelsy MittauerBy Ginger Allen

TARRANT COUNTY, Texas (CBSDFW.COM) – What happened to Caleb Diehl? It’s a question family members of the missing North Texas teenager ask themselves every day. They now have even more questions after learning the 18-year-old was molested years before he disappeared.

Caleb Diehl (courtesy: Diehl family)

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Caleb grew up in Nocona, a small town in Montague County located about an hour north of Denton. He had four older siblings and a big sense of adventure, said his mom. “He had no fear,” said Tami Diehl. “If one of the big kids was doing it he was going to do it too, even when he was little bitty.”

Diehl said most days he could be found with his friends, the Howard brothers. “Our two boys were the same age as their two boys, so it just seemed to work that we would do stuff together.”

The Diehls and the Howards spent lots of time together over the years, even vacationing together. The father, Ricky – a well-known businessman and former bank president – paid the boys to do chores at his properties. “He was just somebody you felt like would do anything for you, if you asked,” said Diehl.

Caleb was still doing odd jobs for Howard when he disappeared. Caleb left his mom’s house around 5 p.m. on Monday, March 30, 2015. He was driving a pickup he had borrowed from Howard while his own was under repair. His sister said Caleb told her he was hanging out with a friend and would be home later. But he didn’t come home that night, and he didn’t go to school on Tuesday.

“His phone was just going straight to voicemail,” said Diehl. On Wednesday she went to the Nocona police station to file a missing person’s report. She said she called Howard to let him know police would be calling for the truck’s license plate number. Diehl said that afternoon, Howard called her back and said the pickup had reappeared.

What happened to Caleb Diehl? (credit: Montague County DA’s Office)

Diehl and police went to Howard’s shop and found the truck parked inside, with the keys hanging where they were normally kept. But there was no sign of Caleb. Former Montague County DA investigator Kevin Benton said police tracked Caleb’s cell phone to the property just before it lost signal. Howard told police he’d found a broken phone on the floor and thrown it away.

“There were several things that obviously raised red flags,” said Benton. “The next day after law enforcement gets involved, Howard gets rid of his own phone. He takes the SIM card out and cuts it up into little pieces.”

Police searched all three of Howard’s properties. Benton said on one of them officers found a burn pit with three computer towers inside. Howard told them the electronics had belonged to his deceased parents.

The Diehls confronted Howard but said he told them he didn’t know what happened to Caleb. Police exhausted all leads; the case grew cold until 2017. Diehl was cleaning her home when she found a plastic bag tucked away in the back of a seldom-used cabinet above her bathtub. Inside was a clock radio with a hidden camera, handwritten notes of polygraph questions, and a tape recorder with audio of a man asking polygraph questions. Prosecutors said the notes were in Howard’s writing and it was Howard’s voice on the tape.

(credit: Diehl family)

When asked what she made of the discovery, Diehl said, “Caleb was collecting stuff. That he was collecting evidence and he was going to tell what was happening.”

Investigators were confused by what the items meant. “That was my question,” said Benton. “Why is [Howard] practicing a polygraph?”

They knew Howard had a criminal history. The longtime banker had pleaded guilty to bank fraud in 2007 and spent two years in prison. What they didn’t know is that his white collar crime had turned up much darker accusations.

The I-Team found court records that show in 2001 an FBI agent investigating Howard for bank fraud spoke with five young men who alleged that Howard had sexually assaulted them. According to one document, the allegations “were each connected to Howard as a bank loan officer or access he gained to the victims through a customer’s children due to his position at the bank. Each victim independently told details of sexual molestation by Ricky Howard during the time they were in their teens and when they began working for him on his ranch.”

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Howard’s former attorney filed an affidavit in a later case, saying he was told the FBI agent suspected “loans may have been made to family members of those young men in an effort to secure their silence.” That affidavit was in response to a motion by Howard claiming the attorney had provided ineffective counsel.

While federal prosecutors charged Howard with only the financial crimes, the judge ordered him into sex offender treatment – with regular polygraph testing – as part of his parole.

WEB EXTRA: Howard’s bank fraud sentence terms (PDF)

WEB EXTRA: Howard accused of faking memory loss (PDF)

“So now we know why he’s practicing polygraph exams,” said Benton. Benton said a judge granted them access to Howard’s treatment records. They reached out to the therapist who told them Howard was a “very clever man” who had “attempted to manipulate the test.” The therapist said there was “no doubt in his professional opinion that Howard had sexual interest in underage males.”

“The sex offender treatment records made it clear that there was a possibility that there was child pornography,” said Investigator Chris Hamilton.

WEB EXTRA: 2018 search warrant lays out investigation (PDF)

Investigators obtained search warrants for two computers once owned by Howard and said they found hundreds of images of child pornography, including photos of Caleb being sexually abused. They believe the pictures were taken during the same time that Howard was in sex offender treatment. Caleb was between 13 and 15 years old at the time. “I was pretty much in denial until I saw the actual pictures,” said Tami Diehl. “It was just like all of the sudden it became very, very real.”

The discovery brought new, painful questions about just how much she didn’t know. “I’ve had so much guilt and regret for not knowing. I just feel like I should have known,” said Diehl. “I mean, he was my baby.”

Howard was charged with sexual exploitation of a minor. His first trial ended in a mistrial this summer when a juror was injured and could not be replaced. Howard agreed to plead guilty in exchange for several other charges being dropped. Among them: charges related to two men who said Howard molested them in the 1990s.

In October, the Diehl family attended Howard’s sentencing at the federal courthouse in Fort Worth. Several relatives of other men who had accused Howard of molesting them came to show support. The judge sentenced Howard to the maximum: 30 years in prison.

(credit: Montague County Jail)

The hearing brought some closure but for the Diehl family the case will never be closed – not until Caleb is found. “I hope for that phone call every day that says ‘we found this. We found something that will tell us,'” said Diehl. “Because it’ll be hard living with never knowing, if that’s what we have to do.” While she will never give up, Diehl said she’s had to make peace with not knowing. “This might be all we have and we might have to make that enough.”

Investigators said the missing persons case is still open. If you have a tip about Caleb’s disappearance, you can email DA Investigator Chris Hamilton at chris.hamilton@co.montague.tx.us. You can also submit anonymous tips through Montague County Crime Stoppers at 866-499-8477.

Howard has not publicly commented about the abuse allegations from the 1990s. His current attorneys did not respond to questions about those allegations, Caleb’s disappearance, or the photos of Caleb and Howard but did share this statement.

“After a mistrial was granted this summer, plea negotiations among all interested parties began in earnest. Federal prosecutors met with the Diehl family and the elected District Attorney for Montague County, as well as investigators involved in all of the cases. In exchange for Mr. Howard’s guilty plea to one count, the federal authorities offered to dismiss all remaining federal counts, and the Montague County DA agreed to dismiss all state charges – amounting to more than 40 additional charges. There are many considerations that factor into whether or not to retry a case. In the end, Mr. Howard elected to plead guilty to prevent his family from enduring a second trial. The plea provides Mr. Howard with the hope of being released in the future, which would not have been possible with multiple stacked sentences.”

— Attorneys Christy Jack, Letty Martinez and Benson Varghese

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