"I can't even express how hard this journey has been and the hundreds of people affected by one person's choice to take my daughter's life," Dodge said during a police press conference in 2017.
Angie Dodge was 18 years old when she was killed at her Idaho Falls apartment in June 1996. The teen was stabbed multiple times, according to investigators.
"They cautioned me that it was a pretty graphic and violent scene -- a lot of blood," said Idaho Falls detective Jeff Pratt. "It was probably the worst case I've ever seen. It's the nightmare."
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Carol Dodge said her daughter had moved out of the family home just three weeks before she was killed in her new apartment. Angie Dodge had moved out after the two disagreed over a house rule, her mother said.
On Angie Dodge's last night alive, she had visited her mother and the two made amends.
"The night that she came over, I rocked her and I said, 'I'm so glad you're not mad at me anymore,' and she just looked up. She said, 'Not even in a blue moon,'" said Carol Dodge. "The next day, that's when they told me that Angie had been found dead."
DNA tests showed police that the semen, hair, and other DNA samples gathered at the scene belonged to the same suspect, Idaho Falls detective Bill Squires said. In the following weeks, detectives searched for the killer.
"Almost every person that they brought in for an interview, they asked them for DNA," said Squires. "We collected over 100 different DNA samples and there wasn't any matches."
Several months after the murder, investigators believed they'd broken the case when a friend of Angie Dodge, Benjamin Hobbs, was arrested for raping a woman at knife point in Nevada.
Due to the similarities of the crime and his friendship with Angie Dodge, Hobbs became a suspect for her murder, Squires said.
Hobbs was a part of a large group of friends who Angie Dodge often spent time with. Police brought in his friend Chris Tapp, 20, of Idaho Falls, who was a part of the same group of friends, who liked to gather by the Snake River.
Police interviewed Tapp, collected his DNA and administered polygraph tests.Tapp initially denied to police any involvement in the crime, but during the nearly 60 hours of interrogations, including while represented by counsel, his story would change five times, leading police to view him with suspicion.
In Jan.1997, Tapp confessed to being at the scene with Hobbs and another unidentified person, despite neither Tapp's nor Hobbs' DNA matching the collected semen and hair samples. Investigators believed that the mystery third person involved was the DNA match, said Squires.
A month later, Tapps was charged with first-degree murder, rape, and use of a deadly weapon in the commission of a felony. Hobbs was never charged in connection with the crime and denied any involvement.
Carol Dodge went to every day of her daughter's murder trial and was a visible presence in the courtroom.
"She wanted the death penalty. She wanted Chris Tapp to suffer the way her daughter had," said CeCe Moore, a genetic genealogist and ABC News consultant who followed the case.
The jury found Tapp guilty in May of 1998.
"When the jury verdict came down it was just sadness, pure sadness," said Tapp. "I couldn't believe I was going away."
"I can say without equivocation that had Mr. Tapp not confessed, there would have been no conviction in this case," Judge Ted Wood had said during Tapp's sentencing in 1998.
The judge opted against the death penalty and sentenced Tapp to 30 years to life in prison. At the time Tapp was convicted, authorities still believed that Tapp did not act alone.
They continued searching for the other people that might've been involved in Angie Dodge's murder and who could match the DNA found at the scene.
"But nothing happened. Nothing came up. No evidence came forward," said Pratt.
Carol Dodge was frustrated because Tapp's DNA did not match the DNA found at the scene. She knew that another person responsible for her daughter's death was still out there and decided to start investigating herself.
"There is one person who killed my daughter. That's what the DNA shows," said Dodge. "I literally went to the streets. I kept going back and forth... kept reading all of the documents and the different reports that I had accumulated."
Carol Dodge said that she would go to the police station every day to make sure the investigation was on track. She continued to investigate her daughter's murder for another 20 years.
In 2008, a turning point came in her investigation when she decided to study all 60 hours of Tapp's interrogation tapes.
She found discrepancies within Tapp's interview answers and realized he didn't know much about what happened that night.
"Chris Tapp [was] not there," Dodge concluded. "I look at Angie's case and for 23 years I have been trying to put this puzzle together. The center is missing."
Since Tapp was in prison, Carol Dodge contacted Tapp's defense attorney, John Thomas of the Bonneville County Public Defender's Office, who had recently been assigned the case to help with appeals. She told Thomas that she thought Tapp was innocent. In 2013, she and Thomas enlisted the help of Steven Drizin, the co-director of the Center on Wrongful Convictions at Northwestern University Pritzker School of Law, and one of the nation's leading experts on false confessions.
"This was the first time that a victim's mother called me and said, 'I've got real concerns that the man who killed my daughter is innocent and would you take a look at the interrogation tapes,'" said Drizin.
Drizin reviewed the tapes and created a report that would later be used in Chris Tapp's appeals. He found Tapp was threatened with the death penalty and told that he would go to the gas chamber.
"It's clearly the kind of threat that can lead people to give false confessions," said Drizin.
During the interrogations, Tapp had also confessed to holding down Angie Dodge's arms while she was raped and murdered and that Hobbs and a friend of Hobbs was also involved in the murder.
Law enforcement claimed that Tapp volunteered statements implicating himself in the crime.
The Idaho Court of Appeals ruled in 2001 that Tapp's statements during his interrogations were not coerced. Drizin, however, concluded in his 2014 report that there was evidence of coercive behavior from the police against Tapp. He also concluded that there was no evidence that Tapp was at the crime scene or that he participated in the murder.
"The one certainty that emerges from the police investigation is that the rapist and murderer of Angie Dodge is still on the loose," wrote Drizin.
In 2015 the prosecutors office hired an independent investigator to review Chris Tapp's conviction. In his report, the investigator determined that a lot of the information Tapp stated during his interrogation was provided to him by law enforcement and that statements the polygrapher made during the polygraph examinations were coercive in nature. The investigator's conclusion, however, was that Tapp was present when Angie was attacked and stabbed, but questioned his confession about being personally involved in her murder.
Prosecutor Daniel Clark issued his own report in 2016 that determined that the statements Tapp's attorney said were coerced were similar to the statements Chris had made to acquaintances, and concluded there was no new evidence that could exonerate Tapp at the time.
Tapp's attorneys, led by John Thomas, filed a motion in 2016 for post-conviction relief but before the motion could be ruled on Thomas reached a deal with the prosecutor to reduce Tapp's sentence to time served.
"The rape charge is completely vacated, so he's no longer a sex offender, but the murder charge would stay in place. We walk out the doors in the front here with our head held high," said Thomas.
After spending two decades of his life behind bars, Tapp was released from prison in 2017.
"Carol was there, and she was holding my hand," said Tapp. "Her fighting for me to help get released and helping to get something better for me is part of the reason why I'm home today. And I'm greatly indebted to that woman. She has no idea."
Even though he was free, Tapp was still a convicted murderer in the eyes of the community, and he hoped one day to be fully exonerated.
Dodge continued to pursue her investigation with the Idaho Falls Police Department, knowing the man who left DNA at the murder scene was still out there.
Captain Bill Squires of the Idaho Falls Police Department took up the case in 2017. Although Squires and Pratt were both part of the investigation at the Angie Dodge crime scene, they were not involved with any of the subsequent interrogations of suspects.
"We were still trying to search for whoever this person was but we have taken every street to the end and there's nothing else to follow up on," said Squires.
In November 2018, Carol Dodge reached out to world-renowned genetic genealogist CeCe Moore. With the help of Parabon Nanotech, Moore began working with police on the case.
Genetic genealogy compares unknown DNA evidence to public genetic databases to identify potential suspects through their family members. Moore said she started building family trees of people who shared DNA with the unknown suspect and with each other, and found where those intersected in one marriage that dated back to the 1800s.
"I knew the suspect had to be a descendant of that marriage, so I narrowed it down to six men who were descendants of that couple, and five of the six on that list lived over 1,000 miles away -- didn't have any connection to Idaho that we could find. One of them did live in Idaho," Moore told ABC News.
DNA samples were collected surreptitiously by investigators from the man and his son.
However, the Idaho man's DNA did not match the DNA at the crime scene and he was also found not to be closely related to the suspect, said Moore. Although it was a setback, Moore said that she was aware of the fact there could be missing descendants through divorces.
"I knew I could not fail Carol, and Chris needs for the true killer to be found so he can be exonerated," said Moore.
Moore found that one of the men in the family had gotten married early and then divorced. She discovered that a child named Brian L. Dripps Sr. was born shortly after the couple had been separated.
"He was carrying his stepfather's surname," said Moore, who said because he had his stepfather's last name, Dripps did not initially register in her family tree search.
In 2019, detectives went to Caldwell, Idaho, to investigate Dripps.
From one of Dripps' discarded cigarettes, investigators were able to match his DNA to the semen and the hair found at the crime scene.
Police also discovered that Dripps had lived across the street from Angie Dodge when she was killed in 1996 and that he'd moved away from Idaho Falls the year of the murder, police said.
Dripps, who was 53-years-old at the time, was arrested on May 15, 2019, and charged with Angie Dodge's murder and rape. During a police interview, Dripps was confronted with the DNA evidence. He admitted to the crime and said he went into Angie Dodge's apartment alone, and committed the crime alone.
"He kind of slumps a little bit, he was silent for a couple of minutes, and then he just said, 'I did it, I raped her, and apparently I killed her,'" said Pratt. "This was the way to make this nightmare finally come to an end. It was a huge victory for me."
Dripps told police that he had gone to Angie Dodge's apartment with the intention to rape her, but not to kill her, said Squires. Dripps admitted that no one else was involved in the crime.
"Just 23 years ago we were in this same building, hearing the sad news that she was gone," said Carol Dodge during a police press conference announcing Dripp's arrest on May 16, 2019.
"Thanks each and everyone of you guys for putting up with my craziness," she added.
During the same press conference, Idaho Falls Police Chief Bryce Johnson said that this case could not have been solved without Carol Dodge.
"Carol, for 23 years, every second of every day, she has been looking out for her daughter," Johnson told reporters. "This case begins and ends with Carol."
Tapp, who was at the press conference, said he felt an overwhelming sense of relief.
"It was more of the vindication of it all, because I kept telling them I didn't do it for years upon years," said Tapp. "It was good to be there for Carol. Her family can go to bed easier now because they actually have the true killer. There was no hatred, there was no animosity. They were happy to see me."
Tapp was exonerated in 2019. Since then, he has filed a civil lawsuit against the City of Idaho Falls and seven former Idaho Falls Police Department officers.
In response to the lawsuit, the City of Idaho Falls released the following statement:
"The city has an obligation to the public to exercise great care in all legal matters. In any pending litigation, public statements always carry the possibility of being used by the various parties involved to the benefit or detriment of the others, which is why we generally do not provide comment on legal matters. We are aware of the lawsuit and demands being made by Mr. Tapp's attorneys and intend to respond to them through the proper legal channels in the course of the legal process."
The defendants, as a group, have filed a Motion To Dismiss.
On February 9, 2021, Dripps pleaded guilty to the rape and murder of Angie Dodge. In exchange for Dripps' plea, prosecutors are recommending that he serve life in prison, with parole eligibility after at least 20 years.
He is scheduled to be sentenced on April 27, 2021.
"Without Carol Dodge, Angie Dodge's murder would have gone off into the annals of boxes upon boxes in some basement somewhere," said Thomas.
Over the span of almost three decades, Carol Dodge said what kept her going was thinking about the last night that she was able to spend with her daughter.
"If I hadn't had the opportunity to hold Angie in my arms that night and to tell her how much I love her, I don't know that I could have made it," she said. "It's what kept me determined to find out why my daughter was killed."