Ashley Swift always viewed her father as a supportive, caring parent.

He showed her how to change the oil in her car. He helped her get her first job, she said, and then brought her home from there. When it was time for college, they talked about the pros and cons of attending straight out of high school.

But two years ago, 56-year-old David Swift was charged with the murder of another person who had a huge impact on Ashley's life: his wife – Ashley's mother. Karen Swift's mysterious and violent death had remained unsolved for more than a decade, and Ashley, then 20, was stunned by her father's arrest.

Then came another development. David, who maintains his innocence, was acquitted in court earlier this year of the most serious charges – first and second degree murder. But the jury disagreed on the lesser crime of manslaughter. Weeks after a judge invalidated proceedings in the case, David was charged with manslaughter and remains in jail awaiting a new trial.

The ordeal lasted more than half of Ashley's life.

“It's something that's very difficult in the beginning, and it's still difficult, but I feel like over time you get over things,” she told Dateline. But “over and over again, everywhere I go, every school I’ve gone to, every workplace I’ve worked at — it shows up.”

To learn more about the case, tune in to “After the Halloween Party” on “Dateline” tonight at 9 ET/8 CT.

Two turbulent decades together

Karen, a 44-year-old mother of four, disappeared on October 30, 2011, after picking Ashley up early from a sleepover and falling asleep with her at her home in Dyersburg, a small town about 80 miles north of Memphis, Dyer County District Attorney Danny Goodman told the jury in May.

Shortly afterward, Karen's SUV was found nearby with a flat tire, as were both of her phones. Both were damaged, Terry McCreight, chief investigator for the Dyer County Sheriff's Office, told Dateline.

In interviews with local authorities, David said he wanted to help as best he could and detailed the couple's tumultuous two decades together, records show. After marrying in 1989, they had two children and then divorced after he had an affair, he said. They later remarried and had two more children – including Ashley – before Karen had an affair, David said.

When she went missing, David believed she was having a mid-life crisis.

She started drinking, sometimes heavily, he said, and partying with new friends. Weeks before her disappearance, he said, she served him with divorce papers.

Although he believed she was “lost”, he said in one of the interviews: “I still love her and care for her.”

While David told authorities that Karen appeared to have withdrawn from her relationship, her friends told Dateline that she had become more independent, social and confident in the last few months of her life.

To Ashley, who was 9 at the time, her mother was a mom who went to every game and every dance competition — “everything, she was there,” Ashley said. However, she also noticed a change in her mother, she said. Karen went out so often, Ashley recalled, that she tearfully begged her mother to stay home.

There is a lack of evidence

Six weeks after Karen's disappearance, her remains were found near a local cemetery, Dyer County Sheriff Jeff Box told Dateline. The coroner determined she died of blunt force trauma to the head.

Authorities focused on possible evidence linking David to the murder. Karen got hold of one of her two phones to avoid her husband's surveillance and tried to keep it a secret from him, Goodman said at trial. David told investigators he didn't know about Karen's second phone, but authorities discovered the device's number was programmed into David's work phone, the prosecutor said.

And during his interview with authorities, McCreight said, David seemed unable to focus on anything other than his wife's behavior.

“That to me was just a sign that this guy was hiding something,” McCreight said. “He’s covering something up.”

Despite these suspicions, there was no physical or eyewitness evidence linking David to the murder. The investigation stalled.

David moved to Alabama and remarried, Ashley said, and her father remained a dedicated parent, taking her to her job at the grocery store and teaching her to work on her Jeep. As Ashley grew older, she said she wanted to know more about what happened to her mother, but became increasingly hopeless at the prospect.

“I got to an age where I realized I would never know what happened,” she said.

I'm trying to put a puzzle together

When David was arrested and charged with her mother's murder two years ago, Ashley recalled how distraught she was at the development. Her father and stepmother separated, she said, leaving Ashley struggling to care for her younger sister. She was confused too.

“I was trying to figure out why,” she said.

Goodman, the prosecutor, said he believed his predecessor was waiting for evidence that would make the case against David a “slam dunk.” But four years ago, the Covid pandemic led to a slowdown in cases, giving prosecutors time to review 30 large file bins related to Karen's murder, Goodman told “Dateline.”

They hadn't identified what Goodman called “the one big thing” that could be used in the attempt to prosecute David, he said. What they found instead was a mystery with a clear motive.

“I think he saw he was losing control,” Goodman said. “Because in the past, he could control everything Karen did, no matter where she went.”

“He saw that starting to wear off,” Goodman added.

David was so angry about Karen's drinking, partying and impending divorce that he violently plotted her death, prosecutors said when they tried the case earlier this year.

After Karen returned home to be picked up by Ashley, the two fell asleep in the same bed, Goodman said. Goodman claims that at some point that night, David took Ashley into the same room as her younger sister and then dragged Karen from her bedroom to the garage.

The coroner had attributed Karen's cause of death to a fractured skull caused by being crushed, and in court Goodman told the jury that David had used such force in the attack that the fatal blow “collapsed her skull.”

David then allegedly loaded Karen into a car, dumped her body in the cemetery and staged the crime to make it appear that she had been kidnapped, Goodman said.

At trial, prosecutors outlined the circumstantial evidence uncovered more than a decade ago – the possible lie about Karen's secret phone and David's “demeaning” comments about Karen to investigators – and said there was no evidence that she planned to return after her call to go out Ashley. Karen's autopsy revealed she had taken a sleeping pill, prosecutors said, and her phones were inactive when she got home.

Prosecutors also brought up an important new detail about Karen's secret phone. Although there was no activity on her devices after she went to bed with Ashley, a forensic extraction revealed that hours later someone used the secret phone to call the device's voicemail, prosecutors said.

That call was made at 9:55 a.m. Oct. 30 while the phone was connected to Wi-Fi at the family's home, Dyer County Assistant District Attorney Tim Boxx told the jury. Karen was already missing at this point, but her phones had not yet been found.

“We know there was an adult at the Swift home at 9:55 a.m.,” Boxx said.

Question the evidence

In court, defense attorney Daniel Taylor said David was not overly controlling but was genuinely concerned about his partner.

There was no evidence to support the state's description of the murder, Taylor said – no blood in the garage or car and no evidence that David ever left the house. Even the medical examiner who gave Karen's cause of death told the prosecutor he no longer believed she had been fatally trampled, Goodman told Dateline.

The conclusion that a phone call was made to the Swifts' home Saturday morning was based on unreliable evidence, Taylor said. He added that David's physical condition would have made it impossible to commit the type of crimes Goodman alleged. At the time of Karen's death, David had re-injured his knee and had to use crutches, Taylor said.

At trial, David's physical therapist testified that he had extreme difficulty walking and lifting. (Goodman accused David of faking the re-injury and said he was seen moving hay bales the day before the murder.)

Ashley, who testified in court, also denied the prosecutor's allegations. It was not David who moved her that night, she testified. It was her mother.

“I will go to my grave knowing that it was my mother,” she told Dateline.

Ashley believed that her father's injury was the strongest evidence that cast doubt on the prosecution. Her mother was athletic, Ashley said, and she couldn't imagine that someone in her father's condition could easily overtake and move her.

After five days of testimony and two days of deliberations, the jury reached its decision and acquitted David of murder, but remained deadlocked on the involuntary manslaughter charge. A date for his retrial has not been set.

Ashley, now a dental hygienist in Alabama, recalled the difficulty of waiting for the verdict and, once it was announced, initially believing the case was over. Then she learned that wasn't the case. David is innocent, Ashley said, and she believes her father was falsely imprisoned while awaiting a new trial.

This reality has made it difficult for her to move on.

“I want justice for my mother and I want my father to be home,” she said. “But I want to live a normal life.”