Seventy-five years after its publication, “The Diary of Anne Frank” remains among the most widely-read books in the world. Blinkering between hope and despair, the account of a Jewish teenager’s life in hiding in an annex behind an Amsterdam warehouse, gave voice and a face to millions of victims of the Nazi genocide, yet one question has gone stubbornly unanswered all these years: who alerted the Nazi search team, in 1944, to Anne Frank and her family’s hiding place? Two Dutch police inquiries and countless historians have come up with theories, but no firm conclusions… Then, in 2016, a team of investigators, led by a veteran FBI agent, decided to bring modern crime-solving techniques and technology to this cold case. And now, they believe they have an answer—one we’ll share with you tonight—to a question that’s bedeviled historians, and haunted Holland: who was responsible for the betrayal?
Anne Frank
Vince Pankoke had turned in his badge and gun. He was two years into a comfortable Florida retirement, when his phone rang in the spring of 2016.
Vince Pankoke: I received a call from a colleague from the Netherlands who said, “If you– if you’re done laying on the beach, we have a case for you.”
Jon Wertheim: Were you laying on the beach?
Vince Pankoke: I– I was actually driving to the beach. I w– (LAUGH) I wasn’t quite there yet.
Pankoke spent three decades as an FBI special agent, targeting Colombian drug cartels. His work had also taken him to the Netherlands, where his investigative chops left an impression.
Jon Wertheim: Were you looking to get back when he told you what it was about?
Vince Pankoke: After he told me it was to, you know, try to solve the mystery of what caused the raid– for Anne Frank and the others in the annex. I needed to hear more.
Vince Pankoke
Four-thousand miles away, in Amsterdam, Thijs Bayens a Dutch filmmaker and documentarian, had been asking around for a credentialed investigator to dig into a question that he feels Holland has never quite reckoned with, one that gets to the essence of human nature.
Thijs Bayens: For me, it was really important to investigate what makes us– give up on each other. The area where Anne Frank lived is very normal. And it’s a very warm area with the butcher and the doctor and the policeman. They worked together. They loved each other. They lived together. And suddenly people start to betray on each other. How could that happen?
Jon Wertheim: Of the millions, literally millions of stories to come out of the Holocaust, why do you think this one resonates the way it does?
Thijs Bayens: I think right after the war people were shown– the concentration camps, the atrocities that took place, the horror. And, suddenly you find this innocent, beautiful, very smart, funny, talented girl. And she as a lighthouse comes out of the darkness. And then I think humanity said, “This is who we are.
Betraying fellow Dutch to the Nazis was a criminal offense in the Netherlands, but two police probes and a whole library of books dedicated to the Anne Frank case, yielded neither convictions nor definitive conclusions.
Jon Wertheim: This question of who betrayed Anne Frank, that had been investigated for years. What was gonna make your investigation different than the ones before it?
Thijs Bayens: If it’s a criminal act, it should be investigated by the police. So we set it up as a cold case.
Thijs Bayens
Like so many, Pankoke had read the diary in middle school in Western Pennsylvania and it left a mark. There would be no perp walks or busted crime syndicates here, but he was intrigued… cautiously.
Jon Wertheim: You hear, “We’re gonna go back and look at Anne Frank.” And that might have the ring of some schlocky media creation. Did that worry you?
Vince Pankoke: Oh, it did. It did. Because as a career investigator, I didn’t wanna be associated with any type of a tabloid type investigation.
Jon Wertheim: You had to make sure this was serious.
Vince Pankoke: Let’s face it. I mean, the honor of the diary, the honor of– Anne Frank, we had to treat this with utmost respect.
What ultimately sealed it for Vince Pankoke, the guarantee of absolute autonomy. The ground rules: Thijs Bayens would oversee the operation and could film the process for a documentary he’s been making. There would be a book about it, which helped finance the project along with funding from the city of Amsterdam, but this was going to be an independent undertaking with serious investigators. And Vince Pankoke was going to take the lead digging in.
Jon Wertheim: You’d done cold cases before. Before this, what was the biggest gap in time between when you were approached and when the– the crime occurred?
Vince Pankoke: It was about a five year crime at that point.
Jon Wertheim: It’s 75 years. So a little different.
Vince Pankoke: It’s a lot different–
Jon Wertheim: This is more than cold.
Vince Pankoke: This– yeah. This was frozen.
To chip away, Pankoke had to draw up his own blueprint. He knew that there was going to be more information to plow through than any human could handle and that artificial intelligence could be a secret weapon.
An FBI man’s dream team was assembled… an investigative psychologist, a war crimes investigator, historians, criminologists plus an army of archival researchers.
Jon Wertheim: What did all these people with disparate skills bring to this?
Vince Pankoke: They brought a different view. It was all of these skills that help us understand and put into context, a crime that happened, you know, in 1944. We have to look at things differently.
Together, they dove into a familiar story: the Frank family had moved to Amsterdam from Germany to escape the rise of Hitler. They found safety in Holland, where Otto Frank ran a manufacturing business. But then the Nazis invaded in 1940, two years later, the Franks—Otto, wife Edith, Anne and her sister Margot—along with four other Jewish friends of the family went into hiding in an annex behind Otto’s warehouse. Today, it’s preserved as a museum. Dr. Gertjan Broek, a historian at the Anne Frank house, showed us in.
Correspondent Jon Wertheim and Dr. Gertjan Broek in front of the bookcase that hid the entrance to the Franks’ hiding place.
Jon Wertheim: Oh, wow. This– this is the famous–
Dr. Gertjan Broek: This is the bookcase–
Jon Wertheim: –bookcase.
Dr. Gertjan Broek: Th– this is the bookcase. It was used to camouflage the entrance to the hiding place.
The bookcase helped protect the Franks, as did a handful of Otto’s close colleagues at the warehouse who were in on the secret.
Dr. Gertjan Broek: We go inside, mind your head.
Jon Wertheim: Oh, wow.
After the raid, the Nazis took anything that wasn’t nailed down. Recreations show what it looked like. Two crammed floors, 761 days, more than two excruciating years indoors. The office workers brought food and supplies, but the eight in hiding couldn’t make a sound during the day. By night they could listen to the radio, desperately plotting updates from the front on this map.
Dr. Gertjan Broek: Here’s a newspaper clipping from shortly after– D-Day, so June, 1944. With the pins that tried to follow the advances of the allied troops in the days and weeks probably after.
Jon Wertheim: This is June, 1944–
Dr. Gertjan Broek: 4 June–
Jon Wertheim: –so–
Dr. Gertjan Broek: So there’s hope because allied forces are on the way. Their life depended on what would happen.
Anne’s bedroom walls, familiar to any teenager, preserved from the day she was taken away. Here, she chronicled the monotony and the horror of life in hiding. “Outside things are terrible, day and night,” she wrote in January 1943. “These poor people are being dragged away, with nothing but a backpack and a little bit of money.”
Her last entry was dated August 1st, 1944. She was 15.
Jon Wertheim: Take me to the day of the raid. It’s the summer of 1944 and what happens that day?
Dr. Gertjan Broek: It’s a warm day, sunny. And around 10:30, between 10:30 and 11:00, a couple of men walk in.
They were detectives with a Dutch police unit working with the Nazis. An SS officer named Silberbauer led the team. They demanded to be shown around the warehouse.
Dr. Gertjan Broek: They end up in front of the bookcase, which is hiding the entrance to the annex. And it’s important I think to realize that two of the policemen present had been seasoned detectives, well experienced. They had been searching this type of building in the inner city of Amsterdam before.
They knew there was likely something behind that bookcase. The stunned inhabitants they found were marched out. On the floor behind them, Anne’s diary – which a quick-thinking office worker, loyal to the Franks, preserved. Of the eight taken away, Otto Frank was the only survivor. The others were among the 100,000 Dutch Jews – 3/4ths of the country’s Jewish population – to die at the hands of the Nazis. In an interview with CBS in 1964, Otto recounted what happened when his family was put on the cattle cars to Auschwitz a month after their capture.
Otto Frank: On September 4th, 1944, the last transport went to Auschwitz. Well, when we arrived at Auschwitz there were men standing there with clubs — women here, men there. We were separated right on the station, so women went to Birkenau Camp and we went to Auschwitz Camp from the station and I never saw my family again.
After the war, Otto Frank was determined to find out who betrayed the hiding place to the Nazis. It was the question many readers asked after he published his daughter’s diary in 1947. But after a couple of years, Otto abruptly stopped looking—more on that curious decision, later. When Vince Pankoke went to Amsterdam to begin his search, his first stop, naturally, was the scene of the crime.
Vince Pankoke: I called this the most visited crime scene in the world because so many people from all over the world, you know, millions of people come here.
Jon Wertheim: So when you come here for the first time, what are you looking for?
Vince Pankoke: Well, as an investigator I wanna see what’s in the area. Of course I wanna see inside the building. I wanna reconstruct how the actual arrest took place, and who participated in it.
Pankoke and his team spent hours in the annex looking for any clue, however remote.
He also cased the exterior —today almost exactly as it was then.
Vince Pankoke: This is the courtyard that is behind the annex. And it’s– as you can see, it’s totally enclosed. This courtyard area is surrounded by the buildings of the neighborhood.
Jon Wertheim: I’m thinking one cough that gets overheard, one window that happens to be open at the wrong time, the sheer risk factor here is extraordinary.
Vince Pankoke: It is extraordinary. When we first started the case, one of the theories that was out there is that the raid may have been caused by somebody in the immediate area seeing something, hearing something, and reporting it. So, therefore, we tracked and identified every resident that lived in this block and adjacent streets.
Using the artificial intelligence program, Pankoke and his team mapped potential threats. In the courtyard surrounding the annex, they found Nazi party members and even known informants.
Vince Pankoke: All living just a wall or two away from one another. When you take a look at the threats the question isn’t, you know, what caused the raid. The question might be: how did they last more than two years without being discovered?
Jon Wertheim: It strikes me in a case like this, anyone could be a suspect. A Nazi sympathizer, an informant, someone who happens to walk by and hear a cough. How did you navigate that?
Vince Pankoke: We had to consider all those options. The team and I sat down and we compiled a list of ways in which the annex coulda been compromised. You know, was it carelessness of the people occupying the annex maybe making too much noise or being seen in the windows? You know, was it betrayal?
Jon Wertheim: There is a theory out there that no one betrayed the Frank family. This was coincidence, or this was good detective work. You buy that at all?
Vince Pankoke: No. No. I mean, we took that theory apart, you know, bit by bit.
Jon Wertheim: This doesn’t play out the way it does, but for a specific tip.
Vince Pankoke: Exactly.
Vince Pankoke, the 30-year FBI veteran, had worked plenty of cold cases, but none this cold. It had been more than seven decades since Anne Frank and her family had been discovered in their hiding place in central Amsterdam and ultimately put on cattle cars to Auschwitz. As to the question of who betrayed the family to the Nazis, all the witnesses were long dead, their evidence thinned by time, but Pankoke leaned on decades of experience and intuition, starting with the old case files.
Vince Pankoke: In a normal cold case, you go to a file. You pull it out. You read through everything that the previous investigation did. Interviews, leads that were followed up on.
Two previous Dutch police investigations into the raid on Anne Frank’s hiding place – one in 1948 and another in 1963 – were not exactly masterclasses in detective work. And a lot of time had passed.
Vince Pankoke: The files were incomplete. And they were scattered about in probably a dozen different archives. Reports were missing. Witnesses had passed on. Memories had failed.
Pulling from the standard cold case playbook, Vince Pankoke followed up on what leads he could. Otherwise he and his team had to take a fresh approach. They spent years in places like the Amsterdam city archives, where the meticulous Dutch record-keeping used so brutally by the Nazis proved a major asset to the investigation.
Wertheim, Pieter van Twisk and Pankoke
Along with Pieter van Twisk— a veteran dutch journalist who co-founded this project and led the research team—they showed us a trove of items they dug up. Including a residence card belonging to Anne frank.
Pieter van Twisk: You can see here her name: her first name, second name, and her surname; and the date of birth. Here you see “N.I.”, which stands for Nederlands (PH) Israelis (PH)– which is her religion.
Jon Wertheim: “Netherland Israeli.” So this–
Pieter van Twisk: Yeah, I don’t–
Jon Wertheim: –she’s “Jewish.”
Pieter van Twisk: –know why– that’s Jewish, she was Jewish, yeah,
Jon Wertheim: Every Dutch resident had to have one of these?
Pieter van Twisk: Yah. Yah.
Jon Wertheim: This is – This is very detailed, and this has her– her parents’ birthdates on it.
Pieter van Twisk: Yah. That’s, of course, also why it was quite easy for the Nazis to find people in the Netherlands, and to know if who was Jewish, or who was not Jewish.
Jon Wertheim: One piece of paper in the ’40s, and you’ve got everything you could want to know about someone.
Pieter van Twisk: Yah.
The team fed every morsel they could – letters, maps, photos, even whole books – into the artificial intelligence database, developed specifically for the project. Then they let machine learning do its thing.
Vince Pankoke: It would identify relationships between people, addresses that were alike. And we were looking for those connections. Clues to solving this.
Jon Wertheim: Quantify how much time that saved you.
Vince Pankoke: Oh– thousands and thousands of man hours.
Jon Wertheim: This also tells you what’s garbage, what’s excluded, what isn’t gonna help your case.
Vince Pankoke: Oh, yeah, because much of what we do is eliminating the unnecessary.
The team paid particular attention to arrest records from the time. The Nazis were hellbent on ridding the Netherlands of all Jews, part of the Final Solution. By 1942, the Franks were among some 25,000 Jews in hiding across the country. The Nazis were coldly skilled at getting people to talk.
Vince Pankoke: Their typical MO was once they arrested somebody, the first question that was posed to them, “Do you know where any other Jews are in hiding?” So what we did is we chronicled all the arrests prior to and just after the annex raid to try to find any connection, any loose thread that would show us that they went from one arrest to another and then ultimately to the annex.
Jon Wertheim: And the implication is, “I’ll make your sentence more lenient if you give up some names.”
Vince Pankoke: Yeah.
Jon Wertheim: Effective?
Vince Pankoke: Oh, it was very effective.
Before long, suspects emerged. Dozens of them, like Willem van Maaren, an employee in the warehouse where the Franks were hiding, whom the Dutch police had interviewed in their investigations.
Vince Pankoke: He was prime suspect number one after the war. He’s working downstairs in the warehouse. He was very shifty, suspicious. Actually a thief.
Jon Wertheim: So you say shifty, suspicious, thief. And yet, you eliminated him as a suspect.
Vince Pankoke: Not a betrayer, though. He was not antisemitic. He had incentive n– not to betray them because if he did, he woulda lost his job, the business woulda been closed.
Jon Wertheim: What specifically are you looking for when you’re considering suspects?
Vince Pankoke: We’re looking at, did they have the knowledge? We look at their motive. You know, what would the motive be? Were they antisemitic? Were they trying to do this for money? And then opportunity. Were they even in town?
Jon Wertheim: So this — knowledge, motive, opportunity, that’s I’m guessing what you were using when you’re infiltrating drug cartels. I mean, this is standard FBI technique–
Vince Pankoke: It’s standard law enforcement technique.
Bram van der Meer
Jon Wertheim: What kind of a person would betray the Frank family?
Bram van der Meer: You would expect maybe that a very bad person did this, a person with– I would say– a psychopathic mind would- would do this.
Bram van de Meer knows psychopathic minds. He had been an investigative psychologist with the national police force in the Netherlands. On Vince Pankoke’s team, he analyzed the behavior and mindsets of suspects they were considering.
Jon Wertheim: That’s your first instinct? So it had to be a psychopath to do this?
Bram van der Meer: Yeah. But you have to be so very careful. It’s war. You’re surviving. Your day-to-day life is filled with fear. Your family might be arrested the next day. You’re thinking everyday about your own survival. So that’s the context.
Jon Wertheim: In a vacuum it had to be a psychopath to do this. But given the context–
Bram van der Meer: That’s right.
Jon Wertheim: Then what kinda person might do this?
Bram van der Meer: Yeah, and then– and then you end up in– in a situation where it could be anybody.
Over time, their focus shifted to someone who, on the surface, might not have raised suspicions. This suspect wasn’t a neighbor of the Franks and didn’t work for them. But the FBI man’s sixth sense kicked in. Arnold van den Bergh was a prominent Jewish businessman with a wife and kids in Amsterdam. After the invasion, he served on the Jewish council, a body the Nazis set up, nefariously, to carry out their policies within the Jewish community. In exchange for doing the Nazis’ bidding, members might be spared the gas chambers.
Vince Pankoke: We know from history that the Jewish Council was dissolved in late September of 1943 and they were sent to the camps. We figured, well, if Arnold van den Bergh is in a camp somewhere, he certainly can’t be privy to information that would lead to the compromise of the annex.
Jon Wertheim: Was he in a camp somewhere?
Vince Pankoke: Well, we thought he was. So due diligence, we started a search. And we couldn’t find Arnold van den Bergh or any of his immediate family members in those camps.
Jon Wertheim: Why not?
Vince Pankoke: Well, that was the question. If he wasn’t in the camps, where was he?
Turned out, he was living an open life in the middle of Amsterdam, Vince Pankoke says, only possible, if Van den Bergh had some kind of leverage.
Jon Wertheim: To my ears, you’re describing an operator. Is that fair?
Vince Pankoke: I’d call him a chess player. He thought in terms of layers of protection, by obtaining different exemptions from being placed into the camps.
As it happened, Van den Bergh—who died in 1950— had come up before, in a report from the 1963 investigation. Though astonishingly, there was little apparent follow up by police.
Vince Pankoke: We read just one small paragraph that mentioned that during the interview of Otto Frank, he told them that shortly after liberation, he received an anonymous note identifying his betrayer of the address where they were staying, the annex, as Arnold van den Bergh.
Jon Wertheim: Wait, wait. So, in the files, there’s reference to a note that Otto Frank received that mentions this specific name?
Vince Pankoke: Remarkably so. Yes. It’s listed right there.
The note was so striking to Otto Frank that he typed up a copy for his records. Naturally, the veteran FBI man wanted to know: where was that note? Any seasoned investigator will tell you that, ideally, good shoe leather comes garnished with good luck. In 2018, Vince Pankoke and team located the son of one of the former investigators. There in the son’s home, buried in some old files: Otto’s copy of the note.
Jon Wertheim: I just wanna get this straight. You’re talking to the son of an investigator. He says, “Yeah, 50 years ago my dad looked into this and I might have some material.”
Vince Pankoke: Yeah. We were lucky.
Jon Wertheim: You’ve held the metaphorical smoking gun in your hand before in the FBI. This anonymous note. Does it feel like a smoking gun?
Vince Pankoke: Not a smoking gun, but– it feels– like a warm gun with the evidence– of the bullet sitting nearby.
Back at the archives, they showed it to us, Otto’s copy. The team used forensic techniques which they say authenticates it. That handwriting you see: the scribblings of the 1963 detective. The anonymous note informed Otto that he’d been betrayed by Arnold van den Bergh who’d handed the Nazis an entire list of addresses where Jews were hiding.
Vince Pankoke: Whoever it was that authored this anonymous note knew so much that– knew that lists were turned in.
Jon Wertheim: And this is information you were able to corroborate.
Vince Pankoke: Pieter was able to locate, in the national archive, records that indicated that in fact somebody from the– Jewish Council, of which Arnold Van Den Bergh was a member, was turning over lists of addresses where Jews were in hiding.
Jon Wertheim: So what’s your theory of the case here? How and why would Arnold van den Bergh have betrayed the Frank family?
Vince Pankoke: Well, in his role as being a– founding member of the Jewish Council, he would have had privy– to addresses– where Jews were hiding. When van den Bergh lost all his series of protections exempting him from having to go to the camps, he had to provide something valuable to the Nazis that he’s had contact with to let him and his wife at that time stay safe.
Jon Wertheim: Is there any evidence he knew who he was giving up?
Vince Pankoke: There’s no evidence to indicate that he knew who was hiding at any of these addresses. They were just addresses that were provided that– where Jews were known to have been in hiding.
We contacted the foundation Otto Frank started in Switzerland and the Anne Frank House in Amsterdam – neither of which formally participated in the investigation – to try to find out whether they could provide any other evidence that might implicate or clear Arnold van den Bergh. The Anne Frank house said they could not. The foundation is reserving comment until they’ve seen the entire results of the investigation.
The cold case team began to confront the real possibility that Otto Frank might have known the identity of the betrayer. What reason, they wondered, would Otto have had to keep this to himself?
Vince Pankoke: He knew that Arnold van den Bergh was Jewish, and in this period after the war, antisemitism was still around. So perhaps he just felt that if I bring this up again, with Arnold van den Bergh being Jewish, it’ll only stoke the fires further. But we have to keep in mind that the fact that he was Jewish just meant the he was placed into a untenable position by the Nazis to do something to save his life.
The team wrestled with these ethical questions. Thijs Buyens, the filmmaker and documentarian who conceived of the project, wondered whether the revelation would be fodder for bigots and antisemites.
Jon Wertheim: The conclusion was that this culprit was a Jewish man who by all accounts was doing what he did to protect his own family.
Thijs Bayens: Yeah.
Jon Wertheim: What was your emotion when you heard this?
Thijs Bayens: I found it very painful. Maybe you could say I even hoped it wouldn’t be something like this.
Jon Wertheim: Why?
Thijs Bayens: Because I feel the pain of all these people being put in– in– in a situation which is very hard for us to understand.
Jon Wertheim: I suspect when this is revealed people around the world are gonna be uncomfortable with the idea that a Jew betrayed another Jew.
Thijs Bayens: I hope so.
Jon Wertheim: You hope they will be?
Thijs Bayens: Yes. Because it shows you how bizarre the Nazi regime really operated, and how they brought people to do these terrible things. The– the real question is, what would I have done? That’s the real question.
Menachem Sebbag
Throughout the project, Bayens sought counsel from Menachem Sebbag, an orthodox rabbi in Amsterdam who also serves as Chief Jewish Chaplain in the Dutch Army.
Jon Wertheim: Is a greater good being served here?
Menachem Sebbag: I hope so. I truly hope so. I hope that people will understand that one of the things that the Nazi ideology did during the Holocaust was to dehumanize Jewish people. And going back into history and looking for the truth and attaining truth is actually giving the Jewish people back their own humanity. Even if that means that sometimes Jewish people are seen as not acting morally correct. That gives them back their own humanity, because that’s the way human beings are when they’re faced with existential threats.
After years of investigating this seven-decade-old cold case, we had a hypothetical for Vince Pankoke.
Jon Wertheim: You’re back to being an FBI agent. You’ve got this case you’ve built. You’ve got your evidence and you hand it over to the prosecutor, the U.S. attorney. You think you’re getting a conviction?
Vince Pankoke: No. There could be some reasonable doubt.
Jon Wertheim: To be clear, it’s a circumstantial case.
Vince Pankoke: It is a circumstantial case, as many cases are. In today’s crime solving, they want positive DNA evidence or video surveillance tape. We can’t give you any of that. But in a historical case this old, with all the evidence that we obtained, I think it’s pretty convincing.
Now back in retirement, Vince Pankoke thinks he’s glimpsed a new way to thaw cold cases. He marvels that an investigation that put no one behind bars, turned out to be the most significant case of his career and one, he believes, brought an answer to a painful historical question.
Produced by David M. Levine. Associate producers, Jacqueline Kalil and Elizabeth Germino. Broadcast associates, Annabelle Hanflig and Eliza Costas. Edited by Michael Mongulla.