UPDATE June 21, 2019:

The Warrick County Sheriff's Office released its entire document file from the 2014 missing person and subsequent death investigation of 27-year-old Boonville, Indiana woman Kristy Kelley, the Evansville Courier & Press reports.

MORE: Warrick sheriff releases files in Kristy Kelley missing person, death investigation - Evansville Courier & Press

November 8, 2017:

Three out of seven: That's how many people failed a polygraph test given by police in the suspicious case of divorced mother Kristy Kelley.

Crime Watch Daily interviews one of those people as her family tries to solve the mystery of what really happened to her.

A pretty single mother of two young children vanishes after a night of partying at a local bar on Aug. 15, 2014.

Now Kristy Kelley's whereabouts are shrouded in mystery and dark speculation.

Was she abducted? Did she just take off?

Fun-loving and vivacious Kristy Kelley was born and raised in Boonville, Indiana, a hard-scrabble Midwestern coal-mining town.

"Bubbly personality, definitely wasn't afraid to tell you what she thought," said Kristy's father Todd Scales. "I couldn't have asked for a better daughter."

At 27 years old, Kristy had just recently divorced and moved back in with her parents, hoping to jump-start her new single life.

"She was getting ready to go out with her friends, and of course I'd always tease her about, 'Well, who you gonna be with?' And of course being a 27-year-old, she would be, 'Dad, really?'" Todd Scales tells Crime Watch Daily.

That question would soon sound ominous on a steamy night in August 2014.

After hitting a few bars on Boonville's main drag, Kristy and her friends wound up at the local VFW. Bar manager Tommy Mattingly vividly recalls the cute young mom with big blue eyes perched on the barstool.

"She was here and there was another girl with her and a guy with her, and they were having a good time," Mattingly tells Crime Watch Daily.

After a few drinks, the couple left. Kristy lingered past closing time.

"She was setting at the bar and me and my bartender, we kind of had our back turned to her, and I turned around, and I mean she was there one minute and the next minute Kristy was just gone," said Mattingly.

They searched the ladies room.

"She wasn't there so we just assumed then that she had come out and went home," said Mattingly.

But Kristy never said goodbye to either of them, including her friend who was tending bar.

"Never said a word. I never heard one sound," said Mattingly.

The next morning, Kristy's parents drove by the local drugstore where she worked, and noticed her car wasn't in the parking lot.

"We just assumed at this time she was probably at lunch," said Todd.

But Kristy Kelley oddly never showed up for her job.

"She didn't ever just miss work without calling in, something," said Todd.

Todd Scales, a Warrick County Sheriff's Department retired jailer, quickly called his former sergeant.

"I just told him, 'Hey, I think I may have a problem. I think my daughter may be missing,'" said Todd.

Todd soon learns Kristy was partying at the VFW. When he arrives there's no sign of Kristy or her SUV. But in the ladies room, the janitor finds Kristy's abandoned cellphone.

"I think that's when my heart really dropped," said Todd. "For her cellphone to be left behind. It may as well have been surgically attached."

The gnawing in the pit of Todd's stomach quickly turned to full-blown panic. He frantically combed the back roads of town in search of his daughter.

"We were gonna find her, you know. Had to," said Todd.

And within a day or two a massive multi-agency search descends on the close-knit town to help.

"We had aircraft, drones, people on horseback, ATVs, there was hundreds if not thousands looking," said Todd.

"We worked around the clock to find her, it was our number one concern," said Kristy's friend Reagan Fuquay.

With no trace of Kristy Kelley, police order polygraph tests for the last known people to see her alive, including the bar manager, Tommy Mattingly.

"The subject" -- Tommy Mattingly -- "was not being truthful regarding the relevant questions."

"It's either two things," said Mattingly. "It's either whoever give me that polygraph test don't know how to operate that machine; or your machine's broke, 'cause I didn't tell you anything but the truth."

Six more people, including Kristy's ex, were given lie-detector tests. Shockingly, three out of seven failed.

Meanwhile, the feverish search for the young mother continued.

"As time went on, you kind of come to the realization the odds of finding her alive, they diminish. But either way we were gonna find her," said Kristy's father Todd Scales.

But where? When the land hunt yields nothing, the search moves below the water's surface. Investigators scour a lake off of a rural country road, and 32 heart-wrenching days after Kristy Kelley went missing, a grim discovery: Kristy's SUV is pulled from the murky green water. Tragically, Kristy is inside.

"Sheriff Kruse and Lieutenant Brian Flowers showed up at the house, said they believed they might have found the vehicle," said Todd. "You're glad that you finally found her, but the flip side of that -- but you also realize you've lost your daughter."

And less than 24 hours later, more heartbreak. The coroner determines the cause of death as an accidental drowning.

"Pretty quick. The night she was found and they did an autopsy early the next morning and it was ruled an accidental drowning. That was the end of it," said Todd.

An accidental drowning? Todd and his wife were not only shocked, they were downright suspicious. What put their antennae up?

"Gosh, going back to that cellphone being left behind, that was a big red flag," said Todd.

Todd says the circumstances surrounding Kristy's death are as murky as the water where she was found. Desperate for answers, Kristy's parents ask Sheriff Brett Kruse to open the case file so they could review the investigative findings. Strangely their request was denied. The sheriff sealed the record and refused to give a reason why.

"He told me then that 'Todd, you know, sometimes in your youth, you do things that you don't want your parents to know,'" said Todd.

Todd Scales wasn't giving up. Convinced Kristy's death was no accident, he goes on an investigation of his own.

"Every time there is a question, it leads to more questions," said Todd.

Was Kristy Kelley's death a tragic accident or an intentional murder?

The answer to that question depends on who you ask.

Did Todd Scales ever ask the sheriff or any of the deputies point-blank, "Why are you not looking into this death further?"

"To be honest, I never really asked them that question," said Todd. "All I know is I wish the case would be reopened and let's try to find some answers as to why it is sealed."

Kristy's parents always suspected their daughter's death was no accident.

"I just want to know the truth what happened to her. I want to know what happened that night," said Todd.

So desperate to know that Todd and his wife took an extraordinary step, hiring attorney April Edwards to dig for answers possibly hidden in the closed file on their daughter's death.

"Sheriff Kruse indicated to me it was an accident and it was closed," said family attorney April Edwards.

The investigators' theory is that Kristy had too much to drink, veered off the road and landed in the lake.

But Tommy Mattingly the bar manager at the VFW said Kristy didn't seem drunk when he last saw her.

"End of the night, she was walking fine, she was talking fine, you know, she wasn't slurring," said Mattingly.

Investigators do say their theory was Kristy was drunk and she went off the road into the lake and drowned. Do you buy that?

"No," said Todd. "In talking with the pathologist, he explained to me how as the body decomposes it produced ethanol. Ethanol reads as alcohol in your toxicology. Her toxicology was only a 0.112. So she had been probably around 0.05, and that would be nowhere near incapacitated."

Could the answers possibly be hidden in security camera footage, now sealed in the closed file, that captured what appeared to be Kristy as she left the bar?

"She'd leave the VFW, make a right, which would be indicative of her coming toward our house, but yet she's found four miles south of town," said Todd.

The sheriff believes Kristy was speeding southbound on Mount Gilead Road. They say she blew past a stop sign and careened into the lake. But Todd Scales says when he searched the area he made a chilling discovery.

What is significant about this location?

"This is the location where we found parts of Kristy's vehicle. There was a passenger-side fender well, that was later determined that's what it came from," said Todd.

Todd says the fender was from Kristy's own car, far from where she was found dead. More than a mile away from the alleged car crash site.

"When they pulled it from the lake, was a lot more damage than have just been caused by water," said Todd. "This is what led us to look to try to figure out what happened."

And another disturbing find. When Kristy was recovered from the lake, her body had no bruises or injuries that would be expected in a violent car crash.

"Nothing. Nothing to indicate any type of bleeding, contusions, scratches, cuts, not a broken fingernail," said attorney April Edwards. "Her body is pristine. So to me that doesn't make sense."

Edwards says investigators were well aware of another bizarre detail: When they pulled the SUV from the water, the gearshift was in park and her keys were in her pocket.

"Why do you take the keys out and put them in your pocket? Why do you put the car in park?" said Edwards. "That to me is extremely odd. Because I would think most people's instant reaction would be 'Yike, I better get outta here.'"

Even more shocking, Edwards says, Kristy's body was found in the back seat. How does law enforcement theorize she ended up there?

"The information that was made available to me indicates that she could have either crawled there or that she could have floated there," said Edwards. "I'm not sure I buy into the floating theory, because there was a big car seat. She had children."

Which begs the second question: Could Kristy Kelley have been the victim of foul play?

"In my mind, it's possible that somebody abducted her and kept her for a couple of days or a week until they realized that the heat was getting tight and they had to dispose of the car and the body," said family attorney April Edwards.

If Kristy was abducted, who would want to take her? Or was it a random attack by someone much closer to home?

One of Kristy's exes, the father, has been at the department for 30 years.

April Edwards tells Crime Watch Daily that one of Kristy's exes has connections to the sheriff's department investigating the case.

"This particular person made a misleading statement to the people investigating her disappearance," said Edwards. "He'd indicated that she had disappeared before, one time for four days, and one time for two days, when in fact that's patently false."

The FBI did help the family get a hold of the data in Kristy's cellphone, even generating a 6,000-page transcript of her texts. And what was discovered in her digital footprint was chilling.

"Her text messages had reflected that an ex had made some threats toward her within the week before she disappeared," said Edwards.

So far the family hasn't been able to connect the dots on the text exchange. Were they just idle threats, or something far more sinister? Were the texts of a sexual nature?

"There was one shortly before her disappearance, said basically 'You just need to disappear,'" said Edwards. "But I really don't want to go into great detail at this time on that."

That same ex was given a polygraph test. His results came back inconclusive, but there was never any follow-up interview.

"I think that there are motives out there, if the police would look a little further," said April Edwards.

But there are other exes in the picture: one of them admitted to keeping track of Kristy's whereabouts. And Kristy's texts reveal she was texting another guy the night she disappeared. With so many questions, we think it's high time to pay a visit to the sheriff.

We're curious as to why the sheriff just won't hand over the case file to Kristy's parents, so we tried to reach out to him. He did not return any of our phone calls or any of our emails, so Crime Watch Daily visited his office to see if he'll talk to us. The receptionist told us the sheriff was not available.

For now, April Edwards is working to legally open the sealed file legally, with help from a forensic pathologist to subpoena the sheriff's department. And at this point, after three harrowing years with no answers, Todd Scales can only hope that one day he will know the truth about what happened to Kristy Kelley.

"Let's find out what happened, period," said Todd. "I owe it to my daughter, and that's kind of my stance on it, and my grandkids someday are going to want to know what really happened. I want them to have those answers."

People who followed this story when it first hit the news might remember that when Kristy Kelley went missing, there was speculation that her case might be connected to another missing Indiana mother of two. Joelle Lockwood disappeared from the same area just a few weeks before Kristy Kelley. But Lockwood was found alive two months later after police say she was held captive in a cage for weeks by a man in his trailer home. Currently, police believe there is no connection between the two cases.