This story originally aired Dateline NBC on June 13, 2008.
Deep in the archives of the Los Angeles Police Department is a room they call "The Tunnel".
Here in this place are more mysteries than even in Hollywood's storied imagination.
Once these were active investigations. Now, they are as dead as their victims.
And they'll stay dead, unless a cold case detective like Richard Bengston can somehow bring them back to life.
Richard Bengston: We're the last chance homicide detectives, because once we've looked at it, if we can't solve it, then nobody else is going to look at it.
But where to begin? Just in the years since 1960, 9,000 unsolved homicides have landed here in the dust-bin of justice.
Keith Morrison: How do you solve 9,000 cold cases?
Richard Bengston: You know what, you can't. But if you can solve one, one unsolved case that nobody else could solve, then you're ahead of the game.
Keith Morrison: Even though they're that old, because it matters?
Richard Bengston: It doesn't matter how old they are, just bring answers to one family that didn't have answers before.
Or so any cop would hope.
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But in 2002, when Bengston was assigned to a 30-year-old triple homicide, he had no idea that he'd need help from a pair of the most unlikely partners he'd ever encountered: two women who had never met, never knew about each other, lived in different parts of the country. But they did share the very same dark secret about the crimes.
Jeanne Laudenberg: I've kept this inside of me for so many years. Quite a story. Hard to believe it really happened.
Renée Laudenberg: It's frightening and scary and evil and horrible and nightmarish.
No, for all those years, the riddle played hard to get along the docksides and among the blue collar watering holes of L.A.'s port town: San Pedro...
What riddle? The one that spun out through a 1970s string of ugly sex murders...
In 1972 Lois Petrie, a recently widowed woman in her 40s, was killed on the bed of her bungalow.
Two years later, Catherine Medina, a middle-aged laundry worker turned up dead in a park.
A month after that, the nude body of 53-year-old Anna Felch was dumped on the side of a road.
Richard Bengston: They were neat murders. Not a lot of evidence left behind.
The killer had made no secret of his motive. He'd raped them all, and strangled their lives away as he satisfied his sick desires.
Richard Bengston: And the other common denominator was all these ladies were known to hang out in the bars in the San Pedro area, so we had another common link besides all being females between the ages of 40 and 60.
But as Bengston began digging through the original file, he could see why the case had died its own slow death: the killer was clever. He'd covered his tracks.
He left not a single fingerprint, not a witness, not a clue.
And of course, it being the '70s, DNA was not yet even a gleam in some future investigator's eye.
Richard Bengston: I don't know if we knew we had a shot at cracking it. But I enjoy putting the pieces back together, you know, figure out what happened, how it happened.
Pieces? What pieces? Well, no one knew it yet, of course, but there was a piece, a clue, for this unsolved puzzle. It was 2,500 miles away in Pittsburgh, Pa. And it wasn't an it, it was a she: Jeanne Laudenberg.
In the Spring of 2003 Jeanne was living a quiet life, working in the accounting department of a company in downtown. What had happened to her three decades earlier had been firmly planted in the past - an unwelcome memory.
It was right around the time of those murders, back in 1975. Jeanne was a college student. She'd met a guy who lived in California.
So, flushed with love and optimism, they decided to move in together. And that summer - 1975 - Jeanne flew out to the coast, San Luis Obispo, to find an apartment. Her beau was scheduled to arrive in town a couple of weeks later, so his step-father, a man named Adolph, picked up Jeanne at the airport.
Jeanne Laudenberg: He seemed like an elderly fatherly figure, and just really nice. He smiled a lot, he was very kind, and we got along great.
So they did, and Adolph squired Jeanne around town as she found an apartment and then he helped her get it ready for the arrival of his step son.
Jeanne Laudenberg: We went to flea markets together, we did a lot of shopping for the apartment, and we just had a good time together.
Then, just a few days before her boyfriend was due in town, Adolph looked at Jeanne and he was suddenly different.
And he told her a shocking story. A story about a serial killer in the harbor town of San Pedro. A killer who just might have Jeanne square in his cross hairs.
Even 30 years here in leafy, quiet residential Pittsburgh, occupied with a good and comfortable life, could not erase the shadow for Jeanne Laudenberg. The memory is still vivid.
It was 1975. Jeanne had come to California to live with her boyfriend. But before he could arrive, she spent time with his step-father, Adolph.
Jeanne Laudenberg: I thought he was a very nice man.
But she was young and perhaps naive.
Within just a few days after meeting Adolph, says Jeanne, he started acting a little toonice.
Jeanne Laudenberg: I don't quite know how to phrase it, but he had fallen in love with me, or at least he said he had.
Keith Morrison: Did this just come out of the blue, like a thunderbolt?
Jeanne Laudenberg: To me it did. Yeah, I was very surprised.
Jeanne claims she tried to brush him off, but "Amorous Adolph" was smitten and started leaving her love notes.
Jeanne Laudenberg: It was creepy. It was creepy. I mean, this is a fellow who's I don't know how many years older than I. And it was very strange.
And then one day Jeanne and Adolph were in a car together, alone. And he turned his face to her and the words that came from his lips were -- well, what's that phrase? Her blood ran cold.
Jeanne Laudenberg: Adolph had told me that he had murdered four women.
Keith Morrison: Hang on a second. People don't just come up and say, "Oh hi, I really like you a lot. And by the way, I’ve killed four women."
Jeanne Laudenberg: He was driving. I was the passenger. And he said that he had murdered four women. Three were in the L.A. area and one was in San Francisco.
Keith Morrison: Did he say how he killed them?
Jeanne Laudenberg: He had strangled them. He had raped them.
He had? The man she was sitting with in the car -- her intended father in law, the man who'd been coming on to her, making her feel creepy, uncomfortable -- he was a rapist? A serial killer?
She'd never heard of those murders in San Pedro. Surely Adolph must be making it up.
Jeanne Laudenberg: And I didn't believe him at first, not until I saw him angry. I remember very vividly he was banging on the car; he was very upset about something. He seemed very strong. I thought, "Yes, he could be capable of doing this."
During his stunning confession, said Jeanne, Adolph referred to the murders as his "four sins". Now Jeanne worried she could be the fifth sin.
Jeanne Laudenberg: I would go and stay in the library because I was afraid to be alone in the apartment.
And then her boyfriend arrived; Adolph’s step son. And such was his and Jeanne's mutual horror, that the two worked up their courage and went to the local police station. And inside, they revealed what Adolph had told Jeanne.
Jeanne Laudenberg: They didn't believe me. So I really felt they had blown me off and I was angry about it.
The local cops in San Luis Obispo did refer the case to the LAPD, Harbor Division.
And the LA cops took Adolph to headquarters to answer some questions.
He did. He was friendly, apparently forthright. He denied everything.
There was no evidence, beyond that strange episode with Jeanne. And he had no record. So they let him go.
The cold case man, Det. Richard Bengston, read the original report of that interrogation in the case files. And 30 years later, he understood why it happened that way. What else could they do, after all?
Richard Bengston: There was no other evidence that LAPD could find to tie him to any one of these three cases, so at that point you have a he said/she said which would not hold up in court, so these detectives were not able to take that case any further.
Jeanne Laudenberg: And I thought, well, that's the end of it.
It was, needless to say, an uncomfortable summer of '75 after that.
Jeanne got married, but Adolph was not invited. Soon after, she and her new husband packed up and moved to Pittsburgh.
Jeanne Laudenberg: I had hoped I was rid of him.
But a few weeks later, something odd showed up at Jeanne's new address.
Jeanne Laudenberg: I had gotten a postcard saying that he was passing through. I had gotten two or three love letters.
Keith Morrison: He was pursuing you in the mail?
Jeanne Laudenberg: Yes, I was petrified. I was afraid to go about my daily business. I didn't know if he would show up, when he would show up.
In his letters, Adolph apologized to Jeanne, but still expressed his love for her.
Then, the letters stopped coming and Adolph Laudenberg seemed to disappear.
Jeanne moved on, too. She divorced her first husband. But despite her story about Adolph, back in San Pedro, the investigation into the murders of Lois Petrie, Catherine Medina, and Anna Felch also faded away.
Years passed. Priorities changed. There were new murders to solve.
Richard Bengston: So the cases -- all the cases -- went cold.
And the mystery of what happened to those three women in San Pedro sat quietly in its case file, and slowly sank deep into the basement vault of the LAPD. Fini.
And then? It was 2002, 27 years later.
It was, as these things can be, completely unexpected.
A phone call. A shocking story.
And who was it from? Another daughter-in-law of Adolph Laudenberg.
Take yourself back to the Spring of 2002. By then, of course, the case of the San Pedro murder spree had been gathering dust in the cold case files for decades.
But that just happened to be the time when a sweet old man who'd taken up residence with some grandchildren decided to tell his daughter in law a story. Her name is Renee.
Renee Laudenberg: He had a hand on his chin, and looking to the corner of his eye, kinda like that. He said, "Well, I murdered -- I raped and murdered four women in my lifetime."
Keith Morrison, Dateline NBC: Just like that?
Renee Laudenberg: Just like that. But it was like outta one eye. And--
Keith Morrison: You must have thought he was joking.
Renee Laudenberg: I was stunned. It was like someone hit me with a brick. And I kinda lost consciousness for a second. And I said, "You need to say that to me one more time. Did I hear you correctly?" And he said, "I raped and murdered four women in my lifetime."
Of course that sweet old man's name was Adolph Laudenberg.
The very same Adolph who had made the very same confession to his other daughter-in-law, Jeanne, 27 years earlier. Now, Renee Laudenberg was in shock. This was the man she called "Grandpa," even though she was no longer married to his son. The man she trusted to baby-sit her kids, who often took them to school and bought them ice cream.
Renee Laudenberg: We were sitting face-to-face, like we are. And he said, "Then grandpa, if he really did this, show -- how did you do it?" And he said he strangled them. And I said, "How? With a rope?" You know, "did you make a noose? What did you do?" And he said he choked them. And he squeezed -- and I could see these people fighting for their life. And he-- he-- (crying) took a life out of them.
Adolph also told Renee that three of the murders took place in San Pedro, a fourth in San Francisco. Four women. Four sins. Just like Jeanne's story.
Richard Bengston: Here's two women that have come forward almost 23 years apart telling us the exact same story.
Keith Morrison: And they don't know each other?
Richard Bengston: And they've never met each other, and they live across the nation from each other.
Renee, frantic, got out of there. She called the police, and talked to detective Chris Merlo, who looked up the old case, and discovered that Renee had provided specifics that could have only come from the killer.
Chris Merlo: She told me that these ladies were all in their late to mid-50s. She told me all they're females, whites. She told me these ladies frequented bars in the San Pedro area.
It was actually that phone call with Det. Merlo that had re-ignited the case. Now Richard Bengston, who had taken it over, had to be sure: was this for real?
Detectives asked Renee to phone her father-in-law and try to coax out another confession -- this time on tape.
This is the actual conversation.
ADOLPH LAUDENBERG: Hello?
RENEE LAUDENBERG: Grandpa?
ADOLPH LAUDENBERG: Yeah.
RENEE LAUDENBERG: Hi, it's me Renee.
ADOLPH LAUDENBERG: Yeah, how're you doing?
RENEE LAUDENBERG: Oh, I'm all right Grandpa. We need to talk.
ADOLPH LAUDENBERG: Huh?...
RENEE LAUDENBERG: You know you dropped a bomb on me, Grandpa, and I haven't had anybody to talk to for days and I'm just like going to explode here, you know. Are you like, you know, sorry for what you did?
ADOLPH LAUDENBERG: I've took all my problems to the Lord.
RENEE LAUDENBERG: Grandpa, I need to know that everything with me is going to be OK?
ADOLPH LAUDENBERG: Oh, yeah.
RENEE LAUDENBERG: You know?
ADOLPH LAUDENBERG: Oh yeah. Everything is fine, yeah. I take my problems daily to the Lord.
Problems? Was he referring to the four murders he confessed to just days earlier?
RENEE: What about the ones you put on me on Thursday?
ADOLPH: Well, mistakes are made.
Renee Laudenberg: From that point on, it was just bewildering. My whole reality just stopped you know? I was still trying to transfer from grandpa to serial murderer. I had no doubt in my mind that I was next.
Suddenly, after three decades, the San Pedro cold case was as hot as they come.
Richard Bengston: It's our obligation to start over at the beginning. So anybody who was talking -- back to whatever year -- whoever had an interview back then, we go back and re-interview them in person.
First a trip to Pittsburgh to meet Jeanne Laudenberg, who had originally reported Adolph's stunning confession way back in 1975.
Richard Bengston: We just showed up at her doorstep.
Jeanne Laudenberg: I had a feeling I knew what it was about, but I was really waiting for them to tell me.
Adolph. The murders. The confession. After 30 years, it all came rushing back.
Jeanne Laudenberg: They always say once a serial murderer, always a serial murderer. And I'm thinking, "how many other people did he kill over the years?" And, "am I a marked woman? I didn't know what to think. I was very scared.
But, even if Jeanne's story, and now Renee's, were true, it could be dismissed as hearsay. How could police find the sort of evidence that would actually stand up in court?
Jeanne Laudenberg: They had asked me if I had a picture of Adolph. And I knew I did. I don't throw away pictures. And when I went to look for it I not only found the photos of him, I found two other things.
Richard Bengston: She is a person who holds onto everything.
And most of it was in her attic, stashed in a paper bag. The love letters and notes Adolph had left her some 30 years earlier were still there. But what she dug up next was the real stunner.
Jeanne Laudenberg: And I also found my date book. I didn't even know I kept a date book from back them.
Keith Morrison: From 1975?
Jeanne Laudenberg: And it was from 1975.
Keith Morrison: And what was in that date book?
Jeanne Laudenberg: Well, this is the mind-blower. As a code I wrote, "Dad confesses sins." And it was only like a week after I had met him.
Richard Bengston: The date book was our jackpot. In her date book, she had detailed things that were occurring at that time in her life. She used it kind of like her memoirs. She can't make up something, 20 years later.
Keith Morrison: What's the importance of that?
Richard Bengston: It just goes to her credibility. And she's able to produce for us something from that time period that leads to the credibility to what's she's saying.
Intriguing? Oh yes. But incriminating? Not quite. At least, not without some solid forensic evidence linking Adolph Laundenberg to the three San Pedro murders.
But, when Det. Bengston looked closer into Adolph's background, he hardly seemed to play the part of a murderer.
Richard Bengston: Never been in prison. Never been arrested. No parking tickets.
And he even looked kind and trustworthy.
Richard Bengston: Big, gray beard. Gray mustache. If you went to the mall at Christmas time, you could probably put him in a Santa suit and you'd find your kid sitting on his lap. And he probably would act a good Santa Claus, because he was a friendly-type person that everybody liked.
So who was Adolph Laudenberg? By all accounts, he was a popular fixture here in San Pedro. He drove a cab for years. He was known as a World War II vet, a granddad who loved his grandchildren, though he himself was divorced and once in a while it was known he liked to have a drink in the local bars here.
When the San Pedro murder case was re-opened, Laundenberg had left Renee's house, was living in a mobile home and spending most of his time at this Porsche repair shop, run by his pal Tony Ugas.
Tony Ugas: He was like family. I call him pops.
Tony Ugas: The customers that used to come by, they all liked him. They all thought he was a nice guy. He always had a joke.
It didn't exactly fit the profile of someone who strangled and raped three women.
Richard Bengston: It was very hard for us to figure out where in his mind he went wrong with wanting to hurt people.
Could it be the cops were wrong? A serial killer that looked and acted like Santa Claus? To the people who knew Adolph Laudenberg, it sure didn't seem like he was capable of committing any of these crimes.
Tony Ugas: All along, I was just thinking the police is you know just framing some poor guy.
Richard Bengston: Now we're hitting a dead wall, because we have nothing we can test. We have two people who have come forward. But it's probably not enough to take the case all the way through.
And sadly, back in L.A., Bengston found the old case file was not quite as forthcoming as Jeanne's attic had been.
The whole thing looked poised to go cold again.
Cold case detective Richard Bengston had a prime suspect for a series of murders in the seaside town of San Pedro: A seemingly kind old man named Adolph Laudenberg. But he also had a big problem.
Richard Bengston: We needed some physical evidence.
These days detectives like Bengston have come to rely on a very helpful new friend: DNA. A speck of human tissue that wouldn't have been useful as evidence back in the '70s, could solve his case now if he could find it.
Richard Bengston: We had already searched our LAPD evidence. And came up with nothing. All of our evidence had been destroyed.
Keith Morrison: That's not supposed to happen, is it, in murder cases?
Richard Bengston: That's not supposed to happen. Very unfortunate. And we don't know why it happened. But, it's something we had to deal with.
The victims had been strangled, and also raped, meaning the killer must have left behind evidence that could be checked for DNA. Surely it had to have been stored somewhere. There was one last place to look.
Richard Bengston: Typical in sexual assault cases that the coroner will take a sexual assault kit, which involves taking different smears from different parts of the body.
Slides from two of the victims, Catherine Medina and Anna Felch, had already been tested, but the specimens were too old and too degraded to extract any DNA.
What about the slides for Lois Petrie, the killer's first victim? Bengston called the Coroner.
Richard Bengston: He was not able to find anything on the Lois Petrie case, which was our main case that we were looking at. It was gut-wrenching to see that it was all gone and there's nothing we could do with it.
Bengston had one last desperate idea.
Richard Bengston: Well, let's go search again. You know, maybe something else will come out. So, we got to know the evidence clerk at the coroner's office very well. And schmoozed her a little bit into showing us the evidence room.
It's home to hundreds of files and thousands of slides. But finding anything in this musty, murky room was a long shot.
Richard Bengston: And while we're over there, she shows us a filing cabinet. And she opens up the drawer. She says, "Well, there's some evidence in this cabinet that we don't have in our computer system. Maybe you could find something in here."
Keith Morrison: You're talking about -- I mean, those are odds like playing the lottery, though, right?
Richard Bengston: You probably have better odds playin' the lottery.
Still, they'd made the trip over here, after all. Might as well give it one last shot.
Richard Bengston: So, we start thumbing through them.
And there they were. Just sitting there. The Lois Petrie slides from 1972.
Richard Bengston: Whoo. I think I had to sit down when it happened. I couldn't believe it.
But given the useless condition of the other old slides they'd already tested, it didn't seem very promising.
He sent the slides off to the DNA lab and waited. His slides had joined hundreds of others all waiting for answers. Time crawled.
Richard Bengston: If you watch TV, it takes 38 minutes. But, in the real world, it takes six to eight weeks to get things tested.
Then, Bengston finally got the call.
Richard Bengston: Her first words to me are, "You better sit down."..."Oh, this is going to be good." So, she tells me, "We were able to get a DNA profile off those slides.”
Keith Morrison: This is the attacker?
Richard Bengston: This is the attacker. This is a deduced profile, this is the suspect.
Keith Morrison: Wow!
Richard Bengston: Unbelievable.
But there was one more little problem. What Bengston did not have was any sort of DNA sample from Adolph Laudenberg for comparison. And how would he ever get that?
Richard Bengston: And it's not something that we as investigators want to run out and ask somebody for their DNA, because--
KEITH MORRISON: Why not?
Richard Bengston: Well, if you're under the investigation and you think something bad might happen, and you know that you might be responsible for this, I don't think you're going to stick around.
Besides, the law about these things is very clear. Without a warrant, he couldn't just walk up to Laudenberg and grab some DNA. So what could Bengston try?
Well, how about that old reliable staple of police work: coffee and donuts -- and a remarkable sting operation.
Once, in the '70s, he'd been a cab driver, cruising the bars of the L.A. port town, San Pedro.
Twice, he'd confessed to daughters-in-law his sins of rape and murder.
Now Adolph Laudenberg was almost 80 years old, drifting, apparently somewhere in Southern California.
And cold case cop Richard Bengston was trying to be hot on his trail and frustrated.
Richard Bengston: We have the DNA from the slide from the Lois Petrie case. But we're missing one thing. We don't have Adolph Laudenberg's DNA sample to compare to the evidentiary sample we have from Lois Petrie.
So how could Bengston legally get Laudenberg's DNA without him knowing it? And, first, how could he even get close to his suspect without spooking him into running away?
Richard Bengston: We came up with a plan to have an undercover officer meet with him and discuss with him a burglary from motor vehicle problem that was occurring in the area that he was living in.
Keith Morrison: You weren't actually being straight up with this guy.
Richard Bengston: No, no, sometimes, we have to--
Keith Morrison: You lie.
Richard Bengston: -- make false -- falsities.
Keith Morrison: And you're allowed to do that?
Richard Bengston: As long as we don't violate anybody's rights, we are allowed to create ruses in order to help us gain what we need.
Which brings us to undercover surveillance specialist Bob Dinlocker. His assignment was to invent some pretext and lure Laudenberg to a meeting without making him suspicious, then invite him to have a cup of coffee.
Keith Morrison: So, he'd leave his DNA how? When he was drinking?
Bob Dinlocker: When he was taking a sip from the--
Keith Morrison: Leave a little saliva behind?
Bob Dinlocker: Yes.
Keith Morrison: Miniscule backwash?
Bob Dinlocker: Yes.
Keith Morrison: And that provides the DNA?
Bob Dinlocker: Yes, and that's being compared to DNA that was collected 27 years ago.
Richard Bengston: And we only need a couple hundred cells, where you probably have a couple million cells in a drop of your saliva. So we didn't need much.
So the plan, a high tech, DNA sting was hatched. An undercover cop would meet Laudenberg, have a cup of coffee with him, and when Adolph left, he'd pick the coffee cup, bring it to the LAPD crime lab. And the technicians here would extract the saliva from the coffee cup, test it for DNA, compare that DNA to the material found at the crime scene and see if there was a match.
It was an excellent plan. The only trouble was finding Adolph Laudenberg.
He was a transient, living all over sprawling LA County, apparently in a mobile home. But where? Before Dinlocker could run the sting, he first had to find him!
Bob Dinlocker: We made contact with people out there, transient people, street people, people in the neighborhood to see if they're familiar with any type of guy--maybe show the picture.
He looked a bit like Santa Claus. Had he disappeared up some chimney somewhere?
Bob Dinlocker: I was starting to get really concerned that we weren't going to find him or the guy wasn't in the area anymore and this was a really good, really workable case, so there was an anxiety level to try & find this particular person.
For the next three months, Dinlocker cased every transient trailer park from San Pedro to Santa Monica.
Finally, late one afternoon, he got a tip from a woman who had spotted Laudenberg's old white camper.
Bob Dinlocker: So, I gave her my card. A half hour later and I get a phone call on my cell phone. And the caller identifies himself as Adolph Laudenberg! And he agreed to meet me at a coffee shop.
Now, the really tricky part: get the suspected killer's DNA without breaking any of the very particular rules about evidence gathering.
Bob Dinlocker: The primary thing is that for us to collect the DNA sample without notifying him of exactly what it's being used for. It had to be a voluntarily discarded and a completely discarded DNA sample.
Keith Morrison: Otherwise what? Couldn't use it in court? Couldn't use it to get a conviction?
Bob Dinlocker: Couldn't use it in conviction. Right.
Laudenberg himself suggested meeting at a neighborhood donut shop. And there he was, a surveillance camera trained on him through the window there, sipping on a cup of coffee.
Dinlocker walked in. Made contact. Started talking -- about car burglaries.
Bob Dinlocker: I knew going in there that I had to concentrate on keeping Adolph Laudenberg focused on my questions, on my ruse. I knew from experience I can't give him a breath or any gap in our conversation to allow his mind to wander, you know, he can raise an eyebrow and say, "Hmmm, what is he really doing here?"
Dinlocker was on his own. If he had any problems, nobody was there to help, not even Detective Bengston, who was downtown at police headquarters, waiting.
Richard Bengston: It was difficult. I think I sat at my desk on pins-and-needles, waiting to hear what had happened.
Bob Dinlocker: My goal was for him to take many sips of that coffee and then, however it went down, for it to be discarded and keep track of it and collect it.
Things started smoothly. Maybe too smoothly. Because then...
Bob Dinlocker: He says, "I thought you were here, actually, to talk to me about some murders that happened in San Pedro back in the '70s."
Bob Dinlocker: And right away, my heart started pounding and the blood's going up.
Had he seen through the ruse? The whole careful plan seemed to be crumbling.
Bob Dinlocker: If he starts to convince himself that that's why I'm there, there's nothing stopping him with grabbing that coffee and leaving.
Three murders, two witnesses and one coffee cup.
The investigation of a 30-year-old serial murder case now hinged on whether undercover cop Bob Dinlocker could get what he needed from the prime suspect; a man who looked like Santa Claus, of all people. He needed Adolph Laundenberg to leave behind a saliva sample on a Styrofoam coffee cup.
But the well-planned sting operation was already starting to unravel. Suddenly Laudenberg had asked if he was being questioned about the murders. Dinlocker had to think fast.
Bob Dinlocker: My mind was telling me, "get him back on your ruse. Make it believable.” Make it something that a reasonable person would believe, but get him back and answer your questions on your ruse.
And it worked. Laudenberg let the San Pedro murder story drop. He drifted back to the original conversation.
Bob Dinlocker: And as it worked out, the best possible circumstances happened. He got up, apparently forgot about the coffee and just walked away from it. And I followed him out of the restaurant.
And, in a heartbeat, a second undercover cop swooped in and took Laudenberg's cup with the precious saliva sample, then rushed it to the crime lab.
Richard Bengston: We have the sample now. This is our suspect. This is going to be great. All right now, let's wait for the testing to be done.
For the next two months, DNA from Laudenberg's saliva would be extracted, analyzed and compared to the specimen taken from Lois Petrie's body. The entire case now hung on whether these two microscopic specks of evidence would match or not.
The suspect, Adolph Laudenberg, went about his transient life unsuspecting, unaware.
Cold case detective Richard Bengston waited and worried.
Would the DNA from the coffee cup match the sample taken from Lois Petrie's body?
Finally, after six weeks, there was an answer.
Richard Bengston: The evidentiary profile from the Lois Petrie case, from the vaginal slides, is an exact match with the suspect profile of Adolph Laudenberg. Unbelievable! Twenty-something years later, and we finally have answers to one piece of the puzzle.
Once in a very long while, a person in the lonely business of retrieving lost justice has a good day. And this day was certainly one of them.
Richard Bengston: It's so exciting. It's so hard to explain how exciting it is that, for me, it's the answer. It's-- the puzzle is, you know, you can shellac the puzzle, it's in place. It's done. And you can hang it on the wall.
For the next several weeks, detectives put Laudenberg under surveillance and tapped his family's phones, hoping to collect even more evidence. Then, one September morning in 2003, they tracked him down at his friend Tony Ugas' car repair shop.
Tony Ugas: The camper was right here, right along the fence. And that's where they came and arrested him. And this was absolutely a total shock. I didn't believe at all that, you know, he had done that.
A team of officers searched Laudenberg's mobile home, looking for incriminating evidence.
Bengston took his suspect downtown to ask him some pointed questions about the three murders in San Pedro and one in San Francisco.
Richard Bengston: I'm nervous. This is a very important interview. Here you have, sitting in front of you, a person who killed four people. Disrupted four lives. Four families. And you know, you want to get to the answers. You know, you want to know why.
ADOLPH LAUDENBERG: I don't have anything to hide.
DETECTIVE RICHARD BENGSTON: That-- that's fine. I just wanna--
ADOLPH: It's just that, I'm not going to get shook up to where I have a problem.
Richard Bengston: He was a little arrogant. You know. He thought "You've got nothing on me."
DETECTIVE BENGSTON: You didn't talk about with Jeanne the four sins of your life? The four sins that you've committed?
ADOLPH LAUDENBERG: What four sins?
DETECTIVE BENGSTON: The four sins involving the four women that were killed.
ADOLPH LAUDENBERG: Oh I don't, I didn't--.
DETECTIVE BENGSTON: You don't know anything about that?
ADOLPH LAUDENBERG: I didn't kill any four women if that's what you're talking about.
DETECTIVE BENGSTON: Ok.
ADOLPH LAUDENBERG: Yeah. I don't know where you're getting your information from...
But Bengston was still hoping he might hear a confession of this man's four sins. So... he told Laudenberg about the crucial DNA evidence that linked him to the crime.
DETECTIVE BENGSTON: All I wanted to know is the reason why it happened. That's all I wanted...
ADOLPH LAUDENBERG: Can I tell you a reason why something happened that you're saying I did that I have no knowledge of doing other than being questioned about it? Am-- am I a stupid person?
DETECTIVE BENGSTON: I have the truth on my side.
ADOLPH LAUDENBERG: Ok, take it to the Lord and just get me a lawyer and let him talk to you.
DETECTIVE BENGSTON: Alright, well we'll take care of that.
ADOLPH LAUDENBERG: Whatever...
And that was that. No more talking.
Later that very same day, Laudenberg was charged with first degree murder for killing Lois Petrie, the only one of the San Pedro murders in which useable DNA was found.
And justice, as justice will, ground slow.
The case finally went to trial in November of 2006; some 34 years after Lois Petrie was found strangled on her bed.
Laudenberg was 80 by now, frail and feeble. But he cast a baleful eye at the witness box, where both Jeanne & Renee Laudenberg told the court how - twice - 27 years apart, he confessed his crimes to each of them.
Jeanne Laudenberg: It was extremely frightening-- I haven't seen this man in over 30 years...giving me the evil eye. I don't know if he was trying to spook me.
Keith Morrison: Was it like to testify against him?
Renee Laudenberg: It was just what I had to do. I felt protected because now there were detectives involved, and there were main, big people involved that knew my story and believed my story.
The trial lasted three weeks.
Once again, Detective Bengston... had to wait.
Richard Bengston: I had no doubt. Based on the testimony we had from the two ladies, the forensic evidence we had from the DNA.
The jury deliberated just one day. It’s verdict... Guilty: murder in the first degree.
Jeanne Laudenberg: And I was ecstatic. I-- I was so thrilled. It was such a huge relief off my shoulders. I was really, really glad.
Renee Laudenberg: The verdict was more like protection. Because he was where he should be, behind bars. And DNA didn't lie. so it felt safer, a lot safer.
Laudenberg's case is on appeal, but he is currently serving a life term.
Keith Morrison: He did a quarter century of freedom that he shouldn't have had?
Richard Bengston: That's the way I look at it. He's got a lot more freedom than what he gave his victims.
Jeanne Laudenberg has returned to her quiet life in Pittsburgh, 30 years of anxiety over her troubled secret now gone like a puff of wind.
Jeanne Laudenberg: I really hope, now that he's in jail, he's had time to reflect upon what he did, and how many lives he touched through his actions.
And it's still happening, in a way, for Renee and her children. That was Grandpa, after all, who did those things.
Renee Laundenberg: It's a nightmare. It's like living a nightmare. At least a nightmare you wake up. But this goes on for years & years & years. You know? And it's going to take time, to come to terms with all of it.
At the LAPD archives the cold cases still pile up. But there is one less homicide now.
And Detective Bengston attacks the stack of mysteries with the vigor of a man who solved a big one... And provided, finally, some answers for a grieving family.
Richard Bengston: Without Jeanne comin' forward in 1975, and Renee Laudenberg coming forward in 2002, these cases remain in a basement of San Pedro.
Laudenberg has also been charged with that fourth murder in San Francisco, but given his poor health and his life sentence, he may not face trial for that crime. He has not been arraigned, so he has not entered a plea. We should note that never before, in the history of the LAPD, has DNA this old been used as evidence in trial.
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