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Welcome to Postmortem. I'm your host, Ann [music] Marie Green, and today we're discussing the murder of Mary K. Hessie,
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a 17-year-old high school student from Wahoo, Nebraska. She was killed in 1969. 55 years and multiple investigations
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later, one of the very first suspects, Joseph Ambrose, was finally arrested and charged with Mary Kay's murder. Joining
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me now is 48 Hours correspondent Natalie Morales. Natalie, you worked on this uh
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episode. It was I mean, it was a doozy. >> Yes. Uh it was. And good to see you again, Anarie. In fact, this is one of
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the longest cold cases that 48 Hours has been working on. Before we dive deeper,
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just a reminder to everyone, if you haven't listened to this episode of 48 Hours, you're going to find it uh in the
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podcast feed just below this one. Listen and then come on back for this conversation. So, Natalie, you know,
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watching the years tick by, I really didn't think that there was going to be a resolution uh to this murder at all.
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And I wonder what it was that kept detectives coming back to the case over and over again when with each year it
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seemed like it would have been more and more of a long shot to get a resolution.
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>> Yeah. You know, this was a real shock to the town of Wahoo. I mean, it really
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lost its innocence after the murder of Mary Kay Hessie back in 1969. Murders there in this town were very rare. But
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afterwards, people were afraid to go to Wahoo because that's where the girl was murdered. It kind of developed that
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negative reputation and connotation, you know. And if you think back, I mean, this was these were the days 1969, it
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was the Satie Hawkins dance. Girls would bring and Mary Kay Hessie, in fact, was
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bringing her little straw pocket book to school. I remember, in fact, having a bag very much like that. And even the
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the lucky rabbit uh keychain was something that I even had as a kid growing up. >> It was like a time capsule. Um reminding
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us of kind of a much more innocent time. And when you go back to Wahoo, you know,
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it really does look a lot. We compared, you know, the footage throughout the hour from 1969 to then we were a little
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bit of a time lapse to 1999 and here here we are 2026 covering this case again. And really not much has changed.
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A lot of the things there still remain the same. And another interesting people may think, well, Wahoo, why does that
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sound so familiar? Well, David Letterman used to have a shtick on his show where
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he would check in with our home office in Wahoo and we drove past the what was the old phone booth, the old glass phone
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booth that you would see back in the day. And people would put post-it notes on that phone booth. And that was the
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so-called office in Wahoo that David Letterman was referring to. And just to bring people back to the case, this is
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how things unfold that day. March 25th, 1969. Mary Kay's parents reported her missing
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that evening when she failed to come home from school. A witness reported seeing Mary Kay getting into a car with
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two men. Her body is then found in a ditch along a rural road. Uh she has been beaten and she has been stabbed to
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death. >> Yeah, >> we know that when it comes to homicides, you know, those first few hours, those
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first few days, they are crucial when it comes to solving a case like this. Why was it so difficult to sort of nail down
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suspects for this murder in those early days, especially when there was an eyewitness who saw her getting into a
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vehicle? >> Yes. And the police at the time did question all those witnesses. Investigators, you know, went about
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doing the job as best they could back then with the tools that they had. Investigators now looking back on the
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case and the prosecutors, you know, they reminded us 1969, I mean, this type of murder case, a homicide in Wahoo,
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Nebraska, that was unheard of. In fact, the Nebraska State Patrol had just started to broaden the scope of things
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that they got involved with, like criminal investigations. Also, it was it was spread out over various different
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law enforcement departments. You know, the police department covered some of it. The sheriff's office had part of the
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case. The state patrol got involved. And some of the evidence of this case was even sent to the FBI, which was at that
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time under Jay Edgar Hoover. All was sent to J. Edgar Hoover's attention. And the current prosecutors say that the
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evidence was scattered all over the place across these different agencies. So that made sort of pinning down things
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a little more difficult. >> So then what sort of evidence did they have, you know, at that time?
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>> Well, really it came down to analyzing and and taking stock of that crime scene. you know, they saw footprints in
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along the road that showed that it appeared that Mary Kay Hessie um got out of the vehicle and it seemed like she
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was running and they could tell this according to the investigators back then because the strides were long strides um
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and they also saw another shoe print by her footprints. Her her school books were found along the side of the road as
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well as that pocketbook that I mentioned stacked neatly on the road. So investigators believe that the killer
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might have placed them on the side of the road realizing, you know, I've got to get rid of this evidence, but this
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was long before the days of DNA testing. So all of that would be preserved somewhat, but yet it would take years
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for them to go back and analyze and look at the case again using new tools with science advancing and catching up to
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where we are today. I thought it was really interesting that they relied a lot on the polygraph tests and now we
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know polygraph tests are, you know, I don't know how often they're used because we know that people can beat
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them. But Joseph Ambrose, they speak to him at the time. He's 22 years old. He's
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questioned because he was seen talking to Mary Kay weeks before the murder. He tells investigators that he was actually
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hanging out with a friend, Wayne Greaser. They were at a number of different locations the night of the
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murder. Both of the men though take and they pass polygraph tests. Um nowadays polygraphs are usually not admissible in
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court. >> Yeah. And you know today I mean I think scientific research suggests that
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polygraph tests they're generally not reliable as you said people can beat those tests. Also if you're nervous and
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you're taking a polygraph test I don't know if you've ever been hooked up to one of those but you know you get
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nervous when you're taking that. I I had it done once, you know, just as a tool and your levels are spiking just because
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you're nervous and it could change the the polygraph result. Um so Ambrose did pass that original polygraph, but we
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again don't really know what exactly he was asked and um they didn't even look at, you know, Ambrose's car at the time.
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And it's believed, you know, if all of this happened, it happened within the car and outside of the car, that would
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have been the crime scene. And also, they never really compared the shoe print that they found frozen to
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Ambrose's. Although Ambrose was a size 9 and a half, which turns out was the size
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of that print. But it would only be years later now as recent investigators started putting the pieces together that
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they would make that connection. And then in 1999, we have Sergeant Bob Frank. He picks up the case again. And
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48 Hours cameras were actually there following the investigation. That's right. You know, we filmed Sergeant
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Frank. This was back when they formed this this newly formed cold case team to tackle this case. And they worked on it
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for a year because this was a 30-year cold case at the time. So we at 48 Hours back then in 1999 were interested to see
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if the cold case team using DNA technology if they could find any new DNA evidence with the new tools and the
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science. So we filmed the team for quite a while and and it was evident though at
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the time that the case didn't seem to be moving forward anywhere. It remained cold. So the story was really put on the
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shelf. That footage also put on the shelf for us at 48 hours. But like we say, we always like to follow cases for
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as long as we can until there's some sort of resolution. And we became aware that an arrest had been made in 2024.
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And we found all the footage that we had and realized, boy, you know, we do have
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a lot here. And and this would make for a fascinating update. Hm. And in watching the archival footage, I was
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sort of struck by how much access 48 hours had. I don't think we would have the same level of access today. I mean,
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it really was like being a fly on the wall in the investigation as it was carrying on. We we went into the
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interrogation room with them. They made it seem like there was this so-called cold case task force. They waxed up the
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tables, even waxed the chairs so that anybody that they brought in for questioning would be uncomfortable and
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like it would be slick and sliding around. You see a bunch of names up on the whiteboard in the interview room.
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That was again one of the tactics they used just to try to make it seem like, oh, they're making a break in the case.
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Look at these names. Although a lot of the names were fake names. One of the investigators even put his own name on
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the whiteboard. So that kind of insight into a case, I don't think we've we've seen something like that today. Um it
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shows though the lengths that the detectives went through to try to get some sort of break in the case and new
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information. Yeah. And you get some real insight into sort of how they're thinking about this investigation.
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Sergeant Frank scour these old case reports and what he notices is that Joseph Ambrose and Wayne Greaser. They
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keep coming up over and over again in witness statements. So then he interviews people who knew the men at
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the time of the murder. And then eventually he actually travels to Florida to speak with Joseph Ambrose
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himself. And we have some of that sound. >> We have a wonderful thing called DNA,
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right? >> And we're going to be able to show who she struggled with. Okay. Um, again, you know, we have all this little
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bits of information here and there that fit together that you were there. Not necessarily that you did it, but that
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you were there when it happened. >> That's yet to be proven. I mean, I wasn't there. Like I said, I had nothing
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to do with it. Uh, and you're you're free to take blood, anything you want. >> You know, we even had incredible access.
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the the crew that was there following Sergeant Frank at the time. They were parked right outside when when they
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picked up Ambrose up for questioning. Ambrose has always been insistent since shortly after the murder that he had
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nothing to do with this. Um he though, as you heard, seemed to be cooperative. He even offered up his blood, but he
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knew investigators also had a search warrant for his house. So, one of the few times we do see Ambrose get just a
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little bit agitated is when Frank brings up, you know, the man who told authorities that Greaser confessed that
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he and Ambrose had driven Mary Kay to that field area and that it was Ambrose who killed her. However, detectives at
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the time couldn't talk to Wayne Greaser anymore because he had died by suicide in 1977.
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Given all of that, there was no match when it came to the DNA to Mary Kay's books or her clothes. So ultimately, it
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came down to this case once again stalling because, you know, the county attorney at the time felt there just
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wasn't enough to move forward in the case. They also they were working off of a grant. They started to run out [music]
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of money. So in 2000, Sergeant Bob Frank unfortunately had to stop working on the
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case. Welcome back. So, the case is cold and then fast forward to 2015. Enter [music]
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Ted Green. He is an investigator for the Saunders County Attorney's Office and he
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starts looking into the Mary Kay. Hessie murder. This is a small town, I presume,
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with limited resources. yet, you know, they still sort of managed to scr up the money to keep this investigation open.
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How were they able to do that? >> Yeah. You know, I it was up to the prosecutor and like I said, this is a
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case that really hung over the community. So, it was something that always remained on people's minds. Time
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though, as as you know, was not on their side. Witnesses of course were dying, memories are fading, and Ambrose was
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getting old. So prosecutors told us they felt it was now or never. And you know,
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Green was the one who looked back at all the files once again. He had to go scrge
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various bureaus to find all these other pieces of evidence that were were widespread over various departments and
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agencies. And he tried to consolidate it, put it all together. He ended up reintering witnesses again. Um, and what
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started off with just a couple of files ended up being boxes and boxes of files and they really went all out um running
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down leads. Um, in 2019, a tipster reported that they had heard stories about men taking apart a car. green
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feels that the car looks an awful lot like one that Joseph Ambrose had actually driven at the time and that the
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car was pushed into water shortly after uh Mary Kay's murder. This led investigators to search a local
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reservoir. It took 5 years to partially to search and then partially dredge this
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reservoir and really they got scraps. So, as I was watching this though, I I just like I wondered why that was so
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important to them, especially considering that it didn't seem like they got much in the way of evidence.
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>> Yeah. You know, um Ted Green was was adamant that finding the car would be the ultimate piece of the puzzle that he
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really needed. It was what he viewed as the crime scene. He thought also that the murder weapon, the knife, could
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possibly still be in the car. Unfortunately, in this case, they came up with just little scraps of material
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which they felt could have been the material from the seats from the inside of the car because it kind of looked
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like that, you know, the color of the material they would expect. Um, but they didn't get to the bottom of the
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reservoir because they couldn't end up dredging the whole reservoir. Mary Kay's body was exumed for a second
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autopsy. Now, you know, after the body was buried for 50 years, I assumed that there really wouldn't be much in the way
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of evidence because I assumed there'd be more decomposition. Um, but I want to play a portion of the interview that you
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had with Richard Register, the deputy county attorney, and Jennifer Jook, the uh Saunders County Attorney where you
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talk about just how well preserved Mary Kay's body was >> when they revealed her after they took
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off the um the drapings or whatever that uh thing she had on her. Uh her legs looked like she was in in just the day
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before. >> It's remarkable. And >> remarkable. >> The thing that was just frightening is
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all is her goosebumps formed on her legs during the autopsy. >> That's what Ted was saying. I did not
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know that could happen. Almost as if she was her body was trying to tell you something from the grave.
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>> Yeah. Just completely remarkable. I had never heard of that being, you know, a
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possibility that, you know, that the body would have goosebumps like that. But apparently according to the
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prosecutors they said the medical examiner said that sometimes when a body is reexposed to oxygen that it can have
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sort of that that reaction like that. What was fascinating about the second autopsy and what that revealed that
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allowed them to get a much bigger clue into who could have done it was they they noticed there were more stab wounds
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in the autopsy than was initially reported. And also according to investigators, the manner in which Mary
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Kay was stabbed was consistent with how slaughterhouse workers are taught to kill animals. And I bring that up
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because Joseph Ambrose worked on the kill floor of a slaughter house. So he knew how to kill animals. He had the
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weapons and the knives to kill animals. And the way Mary Kay Hessie was killed, according to the prosecutors and the
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medical examiner, upon the second autopsy, they felt that it looked like somebody who knew what they were doing.
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Mhm. So then in 2021, Green travels to Ohio now to interview Ambrose again. Um, this guy kind of gets around because
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every time they try to track him down, he's living in a in a different state. Do we have any idea just what was going
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on in his life over the decades between, you know, Mary Kay's murder and 2021? >> Yeah, I mean, it's it's hard to really
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pin it down. Um, we do know that according to authorities, Ambrose had had six wives. He also reportedly was a
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truck driver perhaps for some of that time, uh, according to the prosecutors. Um, but when Ted Green goes to interview
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him this time, he asked him about claims that people had reported at the time that they had witnessed blood on his car
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around the time of the murder. And Ambrose admitted there was blood on his car because he said he probably ran over
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a deer or a rabbit, but the blood was reported on the back rear fender. And that is not typically where you run over
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an animal. You don't really back up into the animal. You would hit them moving forward. So, the fact that Ambrose said
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yes, that there was blood on his car, Ted Green felt that was a revealing part of the interview,
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>> right? I I just thought to myself, either a deer, a deer or a rabbit. I mean,
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>> yeah, you would think you'd be able to narrow it down and you would remember what you hit.
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>> Yeah. If you hit a deer, you probably uh never forgot that there, you know, but
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>> there's a lot more damage to the car as well. >> Absolutely. So by 2023, Green feels like
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he has compiled enough evidence. He shows his findings to the county attorney and then that's presented uh in
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front of a grand jury and the grand jury indictes Ambrose for firstdegree murder
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for the murder of Mary K. Uh Hessie. Do we know what the collection of evidence was that convinced the grand jury? So,
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it was again Ted Green putting all of the pieces together to to give a fuller picture to this puzzle. He had presented
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new witness statements, Ambrose's interviews because he went back to the old interviews and it compared to what
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Ambrose was telling him now with the new interview. And then, of course, the evidence of the shoe print. Well, Ted
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Green says the shoe prints at the murder scene appear to match Ambrose's size, the size 9 and a half. And also the
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pattern was a prisonisssued shoe that Ambrose who had served time. He was on parole at the time had been new to the
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town, but he had been given a prisonisssued shoes. So it could have matched the pattern that was found at
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the crime scene. So they are preparing to go to trial and then in July of 2025 before the case can uh be heard in a
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courtroom, prosecutors reach a plea deal. So Ambrose agrees to plead no contest to the charge of conspiracy to
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commit first-degree murder. But because the crime was governed by the sentencing
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guidelines in 1969, the charge carries a very light penalty just 2 years behind bars. Ambrose is
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sentenced to the maximum. It's 2 years, right? And with the good time sentencing
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reduction law, Joseph Ambrose sentence was actually cut in half. So, with time served, he was actually released in
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November of 2025, which for the murder that has haunted this town for so long, 55 years, for him to serve just a little
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over a year, you know, for the family, it was a real shock and almost a slap in the face. They were not happy about that
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whatsoever. They wanted to bring the case forward to a jury. They wanted the case to go forward in trial. But
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Ambrose, he said he did take this plea deal because he um because of his age, he was on oxygen. He had some health
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issues. He was in his late 70s. He may not have lived until trial. To this day, though, he maintains his innocence. With
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this plea deal, he didn't really have to talk about the case at all. He didn't have to address
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any of the accusations. He didn't have to reveal any details about the murder. So you can't you can understand why
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viewers and I count myself among them would feel like a little unsatisfied with this result. What the prosecutors
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told us is while they understand and they see the family's perspective, of course they would have loved to have
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been able to have charged him and to really have seen him, you know, go to trial, they do believe Ambrose did this
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um as does the family. But the prosecutors really felt that their case faced several challenges. This is 55
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years later. The possibility of witnesses not being around much longer, might have even died. Uh prior
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statements could be viewed as hearsay and that would be inadmissible in court. You know, the murder weapon also was
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never found. There was no DNA evidence and they weren't confident that they were going to be able to get a
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conviction from a jury. Ambrose h also had an experienced attorney who was provided by the state. That attorney was
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able to get Ambrose the best plea deal possible. It's it's very difficult. Not only is it difficult to investigate
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decades old cases, but it's difficult to put together a 48 hours episode. Um so you guys did an excellent job. I really
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sort of felt like I was transported kind of back in time and then forward again.
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And even though it never went to trial, you know, we did get some answers, >> right? In the end, there is, as you
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said, finally an answer and some form [music] of justice for Mary Kay. Hes murder.
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>> Absolutely. Um, really interesting hour. Natalie, thank you so much. >> Thank [music] you. And if you like this
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episode, please rate and review on Apple Podcast or Spotify.