Pod Insights Park Predators The Ride About this episode On a quiet mountain in eastern Tennessee, three men ride off on all-terrain vehicles for an evening of exploring, fishing, and swimming but never return. When foul play is revealed, what seemed like a straightforward murder mystery turns into a bizarre puzzle that local law enforcement spend nearly a decade trying to untangle. This is the story of the July 1988 Signal Mountain murders.
Transcript 0:00 Speaker 00 Hi, park enthusiasts. I'm your host, Delia D'Ambra. And the case I'm going to tell you about today is one that I've had my eye on for a long time. It's the infamous triple murder case in Signal Mountain, Tennessee, that's likely well-known to residents in the eastern part of the state. This case is actually one I kicked over to Crime Junkie back in the summer of 2021, when the second season of Park Predators was released. Ashley and Britt covered it on their show at a high level to get their listeners geared up for new Park Predators episodes. But I've never done my own deep dive on the story, until now. To really immerse myself in the case, I took a trip to Chattanooga, Tennessee, and the town of Signal Mountain to do research and visit some of the locations associated with
0:45 Speaker 00 the crime. My husband grew up in Chattanooga, so he was more than excited to tag along with me and help take some of the pictures and videos we've put out on social media for this episode. Something important to know about Signal Mountain is that back in 1988, when this crime occurred, it was a very tight-knit community. In many respects, it's still that way today. The town's website estimates that around 8,800 residents live there on Walden's Ridge, which peers down over downtown Chattanooga and the Tennessee River Gorge. Many locals and visitors enjoy hiking or mountain biking the town's 18 miles of trails, which connect to nearby Prentice-Cooper State Forest and Shackelford Ridge Park.
1:26 Speaker 00 In July 1988, though, it seemed every trace of recreational activity in the area came to a screeching halt when three men riding ATVs in the woods vanished, only to resurface in one of the most puzzling mysteries to ever happen in the quiet mountain town. This is Park Predators.
2:27 Speaker 00 After 9 o'clock at night on Saturday, July 9, 1988, a young woman named Paula Griffith stared into the woods next to her parents’ home in Signal Mountain, Tennessee. She was watching eagerly for her husband, 22-year-old Kenneth Griffith, to ride up on an ATV. A few hours earlier, around 6:00 PM, Kenneth, his 24-year-old friend Earl Smock, and Paula’s father, Richard Mason, had left their rural property on three-wheelers, though some sources say four-wheelers. The men had ventured into the surrounding landscape to go for a joyride and intended to do a little evening fishing at a scenic swimming spot known as The Blue Hole, which was about three miles north of the Mason’s home.
3:08 Speaker 00 The trails leading to that destination were ones that Kenneth and Richard had ridden many times before, because Richard, his wife Martha, and Paula, who was married to Kenneth, had lived on Signal Mountain for about 13 years at that point. And Kenneth was from the Chattanooga area. He’d met Paula in high school, and not long after graduating, the couple got married. Paula told producers for the television program Bloodlands that Kenneth had never been the biggest outdoorsman, but over the course of their relationship, he’d grown close with her dad and picked up a lot of skills and knowledge about the outdoors from him. So Kenneth and Richard going out for a quick evening ride in the woods was something fairly routine for them when they were together. Earl was the only newcomer in the group.
3:51 Speaker 00 He’d grown up in Decatur, Tennessee, which is about an hour northeast of Signal Mountain. Even though he had experience riding all-terrain vehicles, he’d never traversed the specific geographic area around the Mason’s property before. But since he had Kenneth and Richard with him, he was good to go. He’d met Kenneth after enlisting in the Air Force, and the pair became good friends while stationed in the same squadron at an Air Force base in the Florida Panhandle. A few days before going out on the ATVs, Earl, Kenneth, and Paula had traveled up from Florida to visit with her folks and have some relaxing downtime. Now, before the three men left to head out on the trails around Signal Mountain that Saturday evening, they'd packed three Diet Cokes and some beers in a cooler,
4:34 Speaker 00 and Kenneth and Earl had put on their Air Force flight suits. Richard had also geared up too, but in a different way. He'd wrapped a .44 caliber pistol he owned in a towel and stowed it beneath the seat of his ATV. None of the source material explains why he armed himself, but I don't believe it was because he expected to run into trouble. From everything I gathered, it appears that him bringing the gun was something that a lot of locals in that rural community did whenever they ventured into the woods. Having firepower within reach was, I imagine, a common practice for folks who wanted to protect themselves against, say, wildlife. The terrain on Signal Mountain is remote in some places and has lots of twists and
5:15 Speaker 00 turns, which are not only dangerous if you don't know what you're doing, but also serve as habitats for natural predators like coyotes, black bears, and bobcats. So having a firearm with you isn't the worst idea if you accidentally disturb one of those animals. Anyway, as Saturday night got later and later, Kenneth, Richard, and Earl never came home. Paula and her mother Martha's curiosity about where the guys were turned into genuine worry by the following morning, Sunday, July 10th, when the men had still not returned. The previous night Martha had tried to comfort her daughter by suggesting that maybe the trio had just decided to camp overnight at Blue Hole, or maybe had been unable to navigate
5:58 Speaker 00 back safely in the dark, so they'd waited until morning. But that rationale quickly vanished when the hours ticked by on Sunday and none of the guys showed up. At that point, neither Martha nor Paula could suppress their gut feeling that something was seriously wrong. So around 9:00 AM, Martha called over to a few friends and neighbors to see if they'd spotted her husband, son-in-law, and Earl, but no one had. Sensing the situation was unusual, people who knew the Masons started a small search of their own. But after a while of doing that and getting the same results, Martha realized she needed to get law enforcement involved and dialed the Hamilton County Sheriff's Department, which is currently known as the Hamilton County Sheriff's Office, and she reported all three men missing.
6:46 Speaker 00 According to police records cited in a book about this case titled "Statement of Facts: State vs. Castile," an officer arrived at the Mason's home to take the missing persons' report at 6:45 PM on Sunday night. Some information he wrote down in that report was that 49-year-old Richard had been riding a red Honda ATV and wearing a blue sleeveless cutoff work shirt, blue jeans, and a blue hat. Kenneth, who had unmistakable bright red hair, had also been on a red Honda all-terrain vehicle and was last known to be wearing his green Air Force flight suit and a white hat with an orange T on the front. Now, to me, just based on that unique description, it sounds like the emblem on Kenneth's hat
7:28 Speaker 00 could have been a Tennessee Volunteers baseball cap, but I'm not 100% sure. It would make sense, though, if it was that school's logo, since Chattanooga is only a few hours southwest of Knoxville. When Earl was last seen, he was also in his flight suit, but he'd been riding a blue and white Honda ATV. According to the coverage, not long after the missing persons' report for the men was taken, the sheriff's department prepared to issue an alert about the men, but before they could, they got another call that wasn't immediately connected to the disappearances, but was certainly out of the norm for the Signal Mountain community. (bell dings) The caller was a man who claimed that shortly after 7:30 PM on that Sunday, along
8:10 Speaker 00 a winding mountain road named Roberts Mill Road, a man and a woman who'd pulled over to check one of their tires had flagged him down and reported that they'd found at least two ATVs tossed down a steep embankment that was adjacent to the roadway. This ravine area was a place people would often illegally dump trash, and it had all kinds of junk in it, but ATVs were definitely atypical garbage, even for that spot. So the couple who'd seen the all-terrain vehicles had felt that the discovery was unusual enough that they needed to flag someone down and get that person to drive to the nearest place with a phone to notify law enforcement. And I know this sequence of events feels foreign to us now in the digital age, but
8:52 Speaker 00 you've got to remember, this was 1988 we're talking about. Cell phones were not a thing yet, so this couple stopping another motorist to help them relay their discovery to police was the best they could do at the time. Anyway, when a deputy with the sheriff's department arrived to the bluff area that overlooked the trash dump, he peered down the slope and saw exactly what had been described to him. At least two ATVs just sitting at the bottom of the embankment, and according to police records cited in the book Statement of Facts, there were also a handful of people loitering in the area who'd remained on scene until authorities got there. Not long after the ATVs were found, two detectives with the sheriff's department arrived at Roberts
9:34 Speaker 00 Mill Road and began investigating. Those guys' names were Larry Snead and Roy Parham. As they looked over the first ATV they came to, they immediately noticed it had what appeared to be blood on it, and nearby was another ATV that also had traces of blood present. Neither vehicle, though, appeared to be damaged, like it had been wrecked. As they continued to work, they checked compartments on the ATVs, and beneath the seat of one of them, they discovered a .44 caliber pistol wrapped in a towel. Not long after making that discovery, they stumbled upon a third ATV further down the slope. But this one had no traces of blood on it. It was as clean as could be.
10:18 Speaker 00 According to Unsolved Mysteries, it didn't take the detectives very long to make the connection between the three abandoned ATVs and the missing persons report for Kenneth, Richard, and Earl. By Sunday night, the two incidents had been linked, and because none of the men had been found yet, the prognosis was looking more and more like something bad had happened to them. But authorities still had a lot of investigating to do. Primarily, they needed to find the three guys, and also figure out how in the world their ATVs had gotten so far from the Mason's home. You see, according to the coverage, where the ATVs were found was about four to five miles southeast of the Mason's property, which was not in the direction of the Blue Hole.
11:01 Speaker 00 Blue Hole was further north of the residence. When detectives informed Martha and Paula about where the ATVs had been found, the women were confused. It just didn't make sense to them that the vehicles had been located so far from where the men had said they planned to go Saturday night. A lead that authorities received rather quickly after that came from two local residents who told detectives they'd heard a volley of gunshots ring out on Saturday night in a wooded area on Signal Mountain known as the Helican. According to a map Unsolved Mysteries created and an article by the Daily News Journal, that area is slightly northeast of the Mason's property and about five miles from the illegal trash dump where the ATVs were discovered.
11:45 Speaker 00 Before pursuing that lead further, though, authorities had the ATVs towed from the ravine so they could be examined more closely for potential evidence. Throughout Sunday afternoon and evening, hundreds of people fanned out to search for the missing men, and a few folks even dove down into the blue hole, but no additional clues surfaced from those efforts.
12:07 Speaker 00 The next morning, Monday, July 11th, searching continued and detectives Snead and Parham ventured out to the rugged part of the mountain where witnesses had reported hearing those gunshots on Saturday night. At that location, they saw an old trail that ran through the woods, a few no trespassing signs, and remnants of two wooden fence posts that were rotted but still standing. Like I mentioned earlier, locals referred to this spot as the helican or the helican gate. When Snead and Parham looked around, they discovered ATV tracks, flies, and over the course of that day and the following day, also uncovered a small cooler and several pools of blood on the ground that looked like someone had attempted to conceal them with vegetation.
12:49 Speaker 00 They also saw suspected drag marks on the forest floor and found at least five spent shotgun shells, as well as three trees near the gate that had been freshly damaged by metal pellets. Putting two and two together, investigators suspected the fresh markings on the trees and the spent shells suggested someone had recently fired a shotgun in the area. And really, it was the discovery of this evidence that told detectives all they needed to know. The helican gate was most definitely a crime scene. They just didn't know who had been harmed there, but their suspicions were growing because further investigation of the site turned up hair, bone fragments with traces of lead on them, and pieces of human brain tissue.
13:31 Speaker 00 Which only fueled investigators' fears that someone, most likely Richard, Kenneth, and Earl, had been severely injured while riding their ATVs there, or they were no longer alive. Hamilton County Sheriff's Department's chief deputy at the time told the Associated Press, quote, "I'm 98% sure somebody's dead. I can't confirm it's three people, but I'd be willing to stake money that one's dead. And I'm reasonably sure we'll find three bodies if we find one." He later continued, "The evidence so far indicates at least one suffered a head wound, another probably had upper body injuries. We believe the bikes were hauled
14:13 Speaker 00 out after this and dumped. We believe the bodies were hauled out and dumped." End quote. When news of what authorities had found at the helicane gate made its way to Martha and Paula, they were, I imagine, shocked and, according to some of the source material, reacted in disbelief. The whole time searches for the missing men had been going on, the women had stayed at home eagerly waiting by the phone to get an update from officials. And I have to imagine they were hoping the news would be positive, but sadly, it wasn't. Now, to handle the size of the investigation and sheer number of people volunteering to help look for Richard, Kenneth, and Earl, the sheriff's office set up a command post
14:55 Speaker 00 at an old school in Signal Mountain. From there, they fielded tips and dispatched search crews. According to the television program Bloodlands, because both Kenneth and Earl were airmen, the Air Force even sent about 100 officers to Tennessee to help scour the mountain. There was also a state marijuana task force in the area patrolling for illegal crops that assisted in the search, but unfortunately, even with all those extra resources, the trio remained missing. Then, on Wednesday, July 13, just two days after the crime scene was discovered at the helicane gate, investigators caught a break in the case, but not one they necessarily wanted to catch.
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16:25 Speaker 00 the gift of quality this holiday season. Download the Quince app for app-exclusive offers or go to quince.com. Get free shipping on your order and 365-day returns. Now available in Canada and the UK, too. And when Quince asks where you heard about them, let them know it was Park Predators. It's the best way to support the show.
16:46 Speaker 01 You know that thing where you're scrolling the internet and suddenly you're three hours deep into a celebrity lawsuit?
16:51 Speaker 02 Where you hear a courtroom term and think, wait, what does that actually mean?
16:55 Speaker 01 I'm Eliza Orland, career public defender.
16:57 Speaker 02 And I'm Taya Johnson, law professor and legal analyst.
17:00 Speaker 01 And on our brand-new podcast, Criminally Online, we break down the law behind the stories you can't stop talking about.
17:07 Speaker 02 No legal degree required, just curiosity. Find Criminally Online wherever you get your podcasts.
17:21 Speaker 00 Around 8:00 PM on Wednesday, July 13, officials in Marion County, which neighbors Signal Mountain to the west, contacted the Hamilton County Sheriff's Department with some grim news. An elderly couple who lived on a rural road about 10 to 12 miles west of the Helican Gate had discovered three men's bodies piled in an illegal trash dump about 200 feet off the road. These witnesses had noticed a really bad smell lingering in the air, and upon further investigation, realized where it was coming from.
17:54 Speaker 00 When detectives arrived at the site, they saw that two of the deceased men were wearing flight suits. And I imagine that was pretty much all they needed to see to know that the victims were Kenneth, Earl, and Richard. When the men were found, they'd been stacked on top of one another, with two on the bottom and one on the top lying across the other two. The chief deputy of the sheriff's department at the time told the Associated Press that there were even some indications that all of the victims may have been bound together at some point. It was apparent from their injuries that they'd each been shot, but in different areas on their bodies. For example, Richard had suffered a shotgun blast to his chest, while Kenneth had been shot in the left side of his head. Earl had one blast to his right shoulder,
18:39 Speaker 00 which wasn't fatal, and another to his chest that appeared to have been fired into his heart while he was laying down. Authorities surmise that after seeing Kenneth and Richard get shot, Earl had likely dismounted his ATV and started running, but the killer or killers had caught up to him. Perhaps most curious of all, though, was the fact that each of the men's shoes had been removed when they were disposed of. The source material doesn't mention that any of the shoes were found near or next to the bodies, so that was definitely a strange detail, and not one that I saw addressed beyond just being initially mentioned. It's weird. Even later reporting on this story just doesn't talk about what happened to these men's shoes. But even as puzzling and bizarre as all the case evidence was, though,
19:24 Speaker 00 investigators were sure of one thing. They had three different crime scenes on their hands. There was the Helican Gate, which was where they believed the three men had been killed. Then there was the big trash dump on Roberts Mill Road, where the ATVs had been found. And then finally, there was the body disposal site, way further west of those two locations. One prominent theory officials on the case believed was that the bodies were always intended to be found. Detectives suspected the same thing about the location where the ATVs were ditched. The growing suspicion was that the killer or killers had scattered the ATVs and bodies so far from each other in an attempt to lead law enforcement away from the initial crime scene, the Helican Gate. But things hadn't exactly worked out that way.
20:10 Speaker 00 A member of the sheriff's department told the Associated Press and Kingsport Times News that most likely whoever had committed the crime had moved the victims on all-terrain vehicles through the mountains' back trails. He said it was unlikely the killer or killers would have loaded the men into a truck or car and risked being spotted while driving on an area roadway. So, to me at least, if that was the case, that suggests whoever did this had to have some knowledge of Signal Mountain and the connecting trails that led from Hamilton County into Marion County, which is where the men were eventually discovered. It seems unlikely that it was someone who wasn't from the area. By July 15th, the Hamilton County Medical Examiner had conducted the autopsies on
20:53 Speaker 00 the men, and his conclusions about their injuries and manner of death were what everyone sort of expected. They'd been shot to death, and most likely died on the evening they disappeared. Theories as to why they'd been murdered were all over the place. One investigator told the Associated Press that detectives weren't ruling anything out, and they were looking into about 15 different theories. Some of those avenues of investigation included sightings of devil worshippers, mysterious heavy equipment being seen on the mountain around the time of the crime, and so on. According to coverage by Bloodlands, Unsolved Mysteries, and The Tennessean, several tips came in about sightings of vehicles and people on Roberts Mill Road on the evening of July 9th.
21:38 Speaker 00 But these sightings were all slightly different. For example, one tipster told detectives that he'd seen two men in a blue or silver, possibly Chevrolet truck with three ATVs in the back, near the bluff where the vehicles were eventually dumped. Around the same time, about a quarter mile down the road, another motorist claimed they'd seen a woman trying to stop traffic on the roadway and using a red-colored Chevrolet to literally block the road. And there was yet another account by someone else who reported something similar but claimed the woman he saw had parked a blue-colored Chevy Nova in the roadway to halt traffic. So yeah, these tips were kind of all over the place, and because there were some discrepancies in the details, authorities didn't know what was legit and where exactly to focus their attention and resources.
22:24 Speaker 00 Another avenue of investigation detectives explored was whether Richard, Earl, and Kenneth had accidentally stumbled on an illegal cannabis grow in the woods and maybe seen something they shouldn't have. But that theory fizzled out pretty quickly when a search of the woods near the key locations in the crime didn't reveal many crops or major drug operations going on. The sheriff's department also looked into whether someone in Kenneth or Earl's lives had been involved in the crime. They considered whether the killer or killers had followed the men up from Florida, but after speaking with Paula and some members of the men's squadron at their air force base, investigators learned that was unlikely. Both men were well-respected and praised for their good reputations.
23:07 Speaker 00 So detectives then focused their attention on at least two men who lived on Signal Mountain who were known for confronting trespassers on properties adjacent to the Blue Hole and the Helican Gate. These two guys' names were Cecil Hickman and Frank Castile. Cecil worked as a caretaker on a large tract of land for a man who owned a lot of property on the mountain. He got very agitated whenever trespassers showed up in the woods. According to one of Richard Mason's good friends, Cecil had had a confrontation with Richard about eight months before the murders. During that run-in, Cecil had shot into the air near Richard and his friend to run them out of an area he didn't think they had the right to hunt in. According to the book Statement of Facts, Cecil had been displaying aggressive behavior
23:52 Speaker 00 like this for several years. So investigators looking into the triple homicide felt like he needed to be looked at very closely as a potential person of interest in the crime. When they dropped by to speak with Cecil, they immediately noticed that he owned a 12-gauge shotgun, which was the type of weapon they believed had been used in the murders. When they questioned him about his prior confrontation with Richard, Cecil admitted that he'd fired his shotgun near Richard and his companion a while back, but there was no outstanding bad blood between them. When authorities pressed him, he vehemently denied any involvement in the murders and even offered up an alibi for his whereabouts on the afternoon and evening of July 9.
24:34 Speaker 00 He claimed he'd been at a tractor pull event in Louisville, Kentucky that Saturday, and a friend of his who was a preacher in Louisville could vouch for him. When investigators followed up to confirm his story, the preacher verified that Cecil had been with him at the tractor pull, and both men had even kept their ticket stubs for the event, which detectives later confirmed with Cecil was true. So as quickly as Cecil seemed to emerge as a possible suspect, he was ruled out. The other guy authorities were taking a close look at was a local landowner named Frank Castile. Frank was a local mechanical engineer who'd recently purchased about 130 acres of land on Signal Mountain where he planned to build a home with his wife and three children.
25:17 Speaker 00 According to the book's statement of facts, written by Frank's son Franklin Trevor Castile, who most frequently I saw goes by Trevor. Detectives had first spoken with Frank on the evening of Monday, July 11th, at the sheriff's department's command post, and then later that same night in a detective's car. Frank had received a call from police earlier in the day asking him to come down to the schoolhouse and answer a few questions. According to the book his son wrote, Frank voluntarily agreed to come by. When his interview got underway, investigators asked him about his property, what he'd been up to on July 9th and 10th, and the types of firearms he owned. All of Frank's answers were pretty straightforward. He explained that on Saturday evening, he'd been celebrating his 22nd wedding anniversary
26:02 Speaker 00 with his wife, Susie, and they'd camped together at a clearing on their property near the Blue Hole. The couple claimed they hadn't heard or seen anything unusual while they were out in the woods. Overnight, their family dog that they'd brought with them had become ill, so around 6:35 the next morning, Sunday, the 10th, he and Susie had packed up his Jeep Scrambler and left the woods, heading in the direction of their house so their dog could take some medicine a vet had previously prescribed for it. On their way home, though, Frank said that Susie realized she'd left her purse at the campsite, so he'd volunteered to let her take the Jeep on up to the house, and he'd walk back to their campsite to get her bag.
26:41 Speaker 00 A little while later, Suzie returned to their campsite and she and Frank spent Sunday morning and afternoon with some of their mutual friends named Ronnie and Brenda Lewis. As far as firearms he owned, he told the detectives that he had a .22 rifle, a .22 pistol, and a 12-gauge shotgun. And it was his shotgun that he'd actually had with him on the afternoon of July 9th. You see, he said earlier in the day, before he and his wife started celebrating their anniversary, Frank said he'd interacted with two young men who'd driven up along his property toward the helican gate. He'd spotted the guys from afar off, and when they got close enough, he firmly informed them that they weren't welcome and could be charged with trespassing if they came back. Before the two strangers left, Frank asked the men to write their names and information
27:26 Speaker 00 down in a logbook he kept as a way to document the frequency of people who were coming and going from the area. Those guys complied with that request and then left. Frank said he then went back to his normal routine of cleaning up the woods and getting things prepared for his camping trip with his wife. When detectives asked Frank if they could take a look at his logbook, he told them they were welcome to, and according to what his son wrote in Statement of Facts, he also allowed them to look over his Jeep Scrambler. Authorities eventually took possession of his shotgun, too. Most of the early news coverage of this case doesn't mention Frank Castile by name, but authorities did tell the press that prior to the bodies being found, they had questioned
28:08 Speaker 00 a man who owned the property adjacent to the helican gate, where Richard, Kenneth, and Earl were believed to have ridden their ATVs. It seems from the source material that investigators learned Frank's name fairly early on in their investigation by checking property and land records, and hearing from people who'd had prior interactions with him for violating the no trespassing signs. During some of these encounters, Frank reportedly was always armed. But despite how interested detectives were in Frank as a potential suspect, they didn't have any concrete evidence or eyewitness accounts that tied him to the crime. According to investigative reports by the Nashville, Tennessee Bureau of Investigation
28:49 Speaker 00 Crime Lab cited in the book Statement of Facts, in early August, when the fired shotgun shells that had been found at the helican gate and lead pellets and wadding that were all there too, were tested against Frank’s shotgun, the results indicated that two of the shells were too destroyed to get conclusive info from, but three had been fired from the same gun. However, it didn’t appear that those three had been discharged from Frank’s firearm, at least not that investigators could say with any certainty. But it’s important to note here that just because these five shells were found at the initial crime scene, that doesn’t mean they were necessarily associated with the murders. They could have predated the crime. Here’s what I mean.
29:34 Speaker 00 There’s always the chance that those shells could have been fired from another shotgun at some point in time before July 9th, since the woods around the helican were used by hunters and locals. I mean, don’t get me wrong, it makes total sense to me that investigators looking into the murders would assume these shells were likely connected to the slangs, but it doesn’t mean they actually were. It’s conceivable that whoever shot Richard, Kenneth, and Earl could have collected spent ammunition after the crime, which to me, kind of fits their pattern of behavior, since we know the killer or killers also took so many other steps to cover up the killings, i.e. spreading the evidence, bodies, ATVs across three different locations.
30:17 Speaker 00 It’s also important to understand that ballistics testing on firearm evidence from shotguns is much more challenging than other types of guns. And that’s because shotgun rounds discharge pellets that sort of spray out in a much wider pattern, versus a handgun or rifle which shoots bullets that have lands and grooves on them that are easier to analyze for unique identifying characteristics.
30:41 Speaker 00 As part of authorities’ due diligence, though, they asked Ronnie and Brenda Lewis, that couple who’d hung out with Frank and his wife on the morning and afternoon of Sunday, July 10th, to do an interview. And the Lewis’s told investigators that nothing had seemed off with Frank when they saw him that day. They described his behavior as “normal,” not acting nervously or unusual in any way. They said he just seemed like a guy who’d camped out overnight. According to investigative reports cited in “Statement of Facts,” later in August, so more than a month after the crime, investigators made copies of Frank and his wife’s fingerprints and searched his Jeep, but test results later revealed no traces of blood staining were on the vehicle.
31:23 Speaker 00 However, because word spread fast on Signal Mountain and residents were desperate to see someone held accountable for the crime, Frank, and the fact that he’d been questioned, his shotgun seized, and his Jeep was searched, his family became a bit ostracized, and he was labeled by the public as “the prime suspect,” even though he wasn’t under arrest for the crime. His son wrote in his book that several residents even went as far as signing a petition and sending it to Frank’s house to make him aware that he and his family were no longer welcome on the mountain. Meanwhile, the sheriff’s department’s investigation was at a standstill. Detectives told the Associated Press and WDEF that they felt like they had a lot of
32:04 Speaker 00 the pieces to the puzzle and might even know who committed the crime, but they needed more evidence to prove it. Tennessee’s governor at the time offered up a $5,000 reward for information, and Crime Stoppers even pitched in another $1,000 to encourage witnesses to come forward. But even when the reward grew to more than $20,000 thanks to other donations, weeks turned to months, and the case remained unsolved with no arrests. Then, in 1989, Unsolved Mysteries began producing a segment about the murders, and when that episode aired in January 1990, the Hamilton County Sheriff’s Department was inundated with more than 100 calls about the case.
32:46 Speaker 00 One of which came from a woman who claimed she’d been the person on Roberts Mill Road the night of the crime blocking traffic with a blue Chevy Nova.
33:01 Speaker 00 There's nothing quite like having pieces in your closet you love and count on for any occasion. Whether you're shopping for yourself or picking out gifts for loved ones, Quince is the perfect place to find versatile essentials this holiday season. Quince makes elevated everyday essentials using luxury materials like Mongolian cashmere, organic cotton, and premium stretch denim. Beyond apparel, they offer hotel-quality bedding, leather bags, and five-star luggage. I personally have several of their white Turkish cotton non-slip bath rugs in our master bathroom as we speak. In my most recent order, though, I went all in on the fall/winter clothing collection. I got this amazing washable stretch silk slip dress that honestly is going to be my go-to for pretty much anywhere.
33:45 Speaker 00 Give the gift of quality this holiday season. Download the Quince app for app-exclusive offers or go to quince.com. Get free shipping on your order and 365-day returns. Now available in Canada and the UK, too. And when Quince asks where you heard about them, let them know it was Park Predators. It's the best way to support the show.
34:07 Speaker 01 You know that thing where you're scrolling the internet and suddenly you're three hours deep into a celebrity lawsuit?
34:11 Speaker 02 Where you hear a courtroom term and think, wait, what does that actually mean?
34:15 Speaker 01 I'm Eliza Orland, career public defender.
34:18 Speaker 02 And I'm Taya Johnson, law professor and legal analyst.
34:21 Speaker 01 And on our brand-new podcast, Criminally Online, we break down the law behind the stories you can't stop talking about.
34:27 Speaker 02 No legal degree required, just curiosity. Find Criminally Online wherever you get your podcasts.
34:42 Speaker 00 According to the coverage about this case, the woman who'd been in the blue Chevy told investigators that the reason she'd blocked traffic on Roberts Mill Road was because her and her husband had been riding around in a dune buggy in the woods and it had broken down.
34:57 Speaker 00 So while she and her husband, or maybe just her husband, worked to put a chain around it to tow it out, she'd positioned their Chevy with the headlights pointed down into the woods. And that had required her to stop traffic on the roadway so no one would hit their car. She said she'd never come forward with this information, even when investigators had announced early on that they wanted to speak with whoever owned the Chevy, because at the time, her husband had recently been released from prison. And she was afraid that if she came forward and told authorities they'd been riding around in the woods on July 9th, investigators would try to pin the murders on her husband because of his past criminal history. In the end, that couple was cleared of any involvement in the Signal Mountain murders, and it was just unfortunate timing that authorities didn't know to disregard the sighting of
35:42 Speaker 00 them and their truck sooner. In 1991, three years after the crime, the case was cold and only growing colder. So the sheriff's office decided to hire an independent investigator to look into the murders. But it doesn't seem like that person made much progress, since no arrests happened in 1991, 1992, 1993, or in subsequent years. But then, in the fall of 1996, more than eight years after the killings, something wild happened. Detective Larry Snead received a phone call from an anonymous woman who told him that he needed to locate and speak with a woman named Marie Hill if he wanted to solve the
36:27 Speaker 00 case. And Larry wasted no time in tracking down a woman named Marie Hill who lived in Chattanooga. When he knocked on her front door, Marie answered, and one of the first things she said to the detective was that she'd been expecting him to come by, which I have to imagine was a statement that probably made Detective Snead's jaw drop.
36:48 Speaker 00 While speaking with Marie, Snead learned that she'd been in a relationship with Frank Castile for several months unbeknownst to Frank's wife. According to coverage by the TV programs Bloodlands and City Confidential, Marie indicated to Detective Snead that she thought Frank might have been involved in the Signal Mountain murders from nearly a decade earlier because she'd gotten several anonymous letters in the mail that outright stated he'd killed the three men. One of her neighbors had also received a letter that suggested in no uncertain terms that Marie was dating a killer. The accusations were concerning enough to Marie that she'd shown the letters to Frank, but he'd seemingly dismissed them as untrue.
37:30 Speaker 00 Over the course of several months, authorities investigated this lead and even sent the letters to the crime lab for DNA testing. And when the results came back, the conclusions were kind of a bombshell. Frank's wife, Susie Castile's DNA, was found on the papers and investigators quickly determined that she was the person behind all of it. But they didn't confront her right away, though. Instead, they set up an elaborate sting operation and wired Marie's house to capture conversations between her and Frank, to see if maybe he'd slip up and reveal something incriminating. That plan sort of blew up, though, on October 12, 1996, when Frank's wife barged in on
38:11 Speaker 00 Marie and Frank at Marie's house late at night and caught the two of them together. Wiretap tapes from that heated confrontation didn't capture Frank stating anything incriminating about the Signal Mountain murders. But his wife did make some comments, like, quote, "I've stood by you for 30 years. I've stood by you through one of the worst things we could ever go through. I had myself drugged down to the police station and fingerprinted because of what you've done." And she also said, quote, "What I went through eight years ago doesn't prove to you that I love you," end quote. Which, like, were definitely declarations that authorities suspected were related to the unsolved homicides.
38:55 Speaker 00 And more than six months later, on April 15, 1997, investigators felt like they had enough circumstantial and physical evidence to make an arrest. So they paid 49-year-old Frank a visit at his job near the city of Red Bank, Tennessee, and took him into custody. He was charged with three counts of first-degree murder for the deaths of Richard Mason, Kenneth Griffith, and Earl Smock. A few days after his arrest, prosecutors announced that the district attorney’s office would not be seeking the death penalty against him. They cited a lack of eyewitnesses, uncertainty about some of the physical evidence, and the victims’ families’ preference for seeing their loved ones’ killer behind bars for life as the reason for not pursuing capital punishment.
39:39 Speaker 00 At his arraignment, Frank pleaded not guilty to the charges against him and was kept in custody under a $450,000 bond. His defense attorney tried to get a change of venue, but that request was denied. Ultimately, Frank’s trial opened in Hamilton County in May of 1998 with jurors that were pulled from another Tennessee county. This compromise was reached after a judge agreed with the defense that Frank likely wouldn’t receive a fair trial if all the jurors were people from Hamilton County who’d been following the nonstop publicity about the case.
40:14 Speaker 00 When opening arguments got underway on May 11, 1998, the state’s case was simple. Prosecutors argued that Frank was overly protective of his property and used the helican gate area—which wasn’t even technically on his land—to confront people he didn’t want using the blue hole. Investigators believed Frank had gotten into it with Richard, Kenneth, and Earl while they were riding on the old logging trail toward the swimming hole. Prosecutors told jurors that Frank had murdered the men and then taken every precaution to ensure their ATVs and bodies would be found far away from his property. Witnesses the state presented to support their version of the crime included a parade of a dozen—though some sources say it was as many as 15—people who had negative
40:57 Speaker 00 interactions with Frank near the helican gate. Marie Hill, his mistress, also testified, as well as the two young men who Frank had confronted earlier in the day on July 9 near his property. Those two guys testified about how frightened Frank had made them feel when he approached them armed with a shotgun and requested they give him their names, license plate numbers, and personal information for his logbook. The prosecution also played the audio tape of the late-night heated confrontation between Frank, his wife, and Marie. But when Susie testified about that whole thing, she told jurors that the claims she'd made in the anonymous letters to Marie and Marie's neighbor accusing Frank of the murders weren't true.
41:40 Speaker 00 She said she just sent the messages to scare Marie and make her think Frank was a bad guy so she'd stop seeing him. According to the coverage, prosecutors and investigators were highly suspicious that Frank's wife, and possibly even one of Frank's other sons, could have played a role in covering up the murders in 1988. But neither of them have ever been charged in relation to this crime. And Frank's wife has always stuck to her story that she and Frank were camping and celebrating their wedding anniversary when the slayings occurred. When Marie Hill took the witness stand, she endured a grueling cross-examination from Frank's defense team, but she maintained that she'd cooperated with law enforcement and allowed detectives to bug her home because she genuinely wanted to know whether the
42:25 Speaker 00 man she'd been having an affair with was actually a murderer. In his own defense, Frank chose to testify too, and vehemently denied any involvement in the murders. But according to his defense lawyer, who later spoke with producers for City Confidential, Frank's demeanor and testimony didn't come off well to jurors. His lawyer said that Frank's rebuttal to all of the witnesses who testified against him about his aggressive presence on the mountain was that they were all lying and he was the only person telling the truth. According to an interview Larry Snead did with City Confidential, there were a few witnesses that didn't testify during the trial. But if they had, they would have unequivocally refuted Frank's version of events.
43:09 Speaker 00 One witness, the Castile's neighbor, told investigators during their investigation that she saw Frank driving his Jeep Scrambler on the morning of Sunday, July 10, and he was coming up from the campsite near the Blue Hole. But he didn't have the family's dog in the bed. Instead, she saw an ATV. She wouldn't commit to testifying to this information in court, though, because she said that the day after she saw Frank allegedly hauling the ATV, she'd received threatening phone calls from an unknown person, and that freaked her out. So after that, she eventually moved to Florida and wanted nothing more to do with the case. A former prosecutor told City Confidential two other critical witnesses that challenged Frank's version of events were a man and a woman who'd been having an affair in the
43:53 Speaker 00 woods on the night of July 9th, and claimed to see a Jeep hauling several ATVs out of the woods. But even without hearing from these additional witnesses at trial, jurors took less than two hours to deliberate and found Frank guilty of all three murders. A judge sentenced him to life in prison with the possibility of parole after 51 years. After the verdict was read, Frank's son Trevor, who's the author of the book I've mentioned throughout this episode titled "Statement of Facts: State vs. Castile," told the press that justice had not been served, and he felt sorry for Kenneth Earl and Richard's families because he wasn't convinced that his father was the person responsible for the three men's deaths.
44:38 Speaker 00 Kenneth's brother Lee told reporters, though, that he wholeheartedly believed Frank was guilty of murder, and seeing him convicted brought some closure to the Griffith family. But not a true sense of peace. He said that he'd spent so much time waiting for someone to be held accountable for killing Kenneth and the other men that, now that it was all over, he wasn't sure what he was going to do with his time. He explained what he was feeling to the Associated Press this way: "I didn't realize how emotionally, physically, and mentally I would be drained by that trial. You stay on guard every day. You're hearing all the stories all over. The verdict was kind of like a salve to a wound that will never be healed. We'll always miss Kenneth.
45:20 Speaker 00 We had dreams of retiring together and watching our kids grow old. It was all taken away from us." Unfortunately, Martha Mason, Richard's widow and Kenneth's mother-in-law, passed away before Frank was found guilty, so she never got the opportunity to see justice carried out. Paula, their daughter and Kenneth's wife, never moved back to Florida after the crime, and eventually remarried.
45:47 Speaker 00 In 1999, Frank appealed his conviction citing that the trial court had improperly allowed prejudicial testimony and even circumstantial evidence like the wiretap tapes in his evidence. In an unexpected twist, the appellate court agreed with some of his arguments and his conviction was overturned in 2001. He was granted a new trial that year with a jury that had been pulled in nearby Davidson County. The second trial got underway in April 2003 and lasted a few weeks, and it went a lot like the first trial. Local residents testified about their prior interactions with Frank in the woods. Marie Hill discussed her role in the police sting, and Frank's wife told jurors that she'd
46:29 Speaker 00 come up with the whole letter-writing ruse to simply force Marie and Frank apart, not to paint him as an actual killer. The only big difference between trial number one and trial number two was that the defense called their own star witness to the stand, who hadn't come forward prior to the first trial. This guy's name was Raymond Harden, and he worked as a junk collector. He told jurors that on the evening of the crime, he was driving in Signal Mountain and saw two men in a black pickup truck disposing of blood-covered ATVs on a local roadway. He claimed to have witnessed this as he drove by in his own car. When he was questioned about why he'd waited so long to come forward with the information,
47:11 Speaker 00 he claimed he'd stayed silent because he was scared. He said he recognized the two men ditching the all-terrain vehicles as the sons of Cecil Hickman. Yeah, the same Cecil Hickman who authorities had seemingly ruled out as a suspect. And according to Raymond, Cecil's sons were, quote, "ruthless people," end quote. So he wasn't keen on ratting on them back in 1988. In the end, though, jurors in the second trial weren't convinced of this new information. In May 2003, they convicted Frank again for the three murders. He appealed that verdict in 2004, but this time, the appeals court upheld his conviction. His attempts to get a third trial were denied.
47:56 Speaker 00 According to the Tennessee Department of Corrections website and coverage by WTVC, Frank died in prison in May 2019. For Kenneth's brother Lee, Frank's death was a relief. Speaking to the impact that the case had on him and his family, he told WTVC in part, “It was like being in a movie that you couldn't turn off. We don't have to devote any more of our lives to this.” In April 2020, Frank's son published his book about the case titled “Statement of Facts: State vs. Castile,” which, though it does cite some investigative reports, is mostly his personal perspective of the events surrounding the crime, his father's arrest, and the two trials. He admittedly states multiple times in the book that a lot of the writing is just his
48:41 Speaker 00 own opinion. “I've read it and agree that some of the tone is very opinionated, but hey, anyone is allowed to write a book.” Whichever side you find yourself convinced of in this case, one thing remains true. Three men were killed on Signal Mountain in the summer of 1988, and for what seems to be no real reason. If it really was a turf dispute gone wrong, that's still so sad to me. Earl and Kenneth were young men with their whole lives ahead of them, and Richard was a loving husband and dad who thought he would be safe in a forest he knew like the back of his hand. If you find yourself in the mountains of eastern Tennessee anytime soon, I hope you'll remember these three men's names.
49:25 Speaker 00 I hope you're reminded of them the next time you hear an ATV's motor crank up. And I hope that this story is a reminder that we never really know what ride will be our last. Park Predators is an AudioChuck production. You can view a list of all the source material for this episode on our website, parkpredators.com. And you can also follow Park Predators on Instagram, @parkpredators.
49:58 Speaker 00 I think Chuck would approve.
50:05 Speaker 03 One day last year, detectives knocked on the door of a multimillion-dollar mansion in Los Angeles County. Inside, they found a strange scene. A dining area converted into classrooms with children and toddlers seated at rows of desks. The couple that lived there had 21 kids.
50:25 Speaker 04 It's a house that looks like a castle, but it's under investigation for being a possible factory, a baby factory.
50:32 Speaker 03 Where had these children come from? Almost all of them were born through surrogates. But those surrogates had been deceived.
50:40 Speaker 05 Me and my coworker, we named her the surrogate pimp. That's the one time that we called the cops because she was screaming. And then he pulled out a gun.
50:48 Speaker 03 I started crying. I was like, what the heck did I just get myself into? I'm Ava Kaufman. The Journey is a new series from In the Dark and The New Yorker. Find it now in the In the Dark feed, wherever you get your podcasts.
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