Led by Vince and with all researchers present, every Monday there would be a plenary research session to discuss the progress of the previous week and the necessary follow-ups and tactics. Occasionally, different experts, such as investigative psychologist and offender-profiling expert Bram van der Meer, would visit, and thoughtful discussions would ensue.
The Amsterdam City Archives became one of the most important sources for research and was like a second home to the full-time researchers. The main archivist, Peter Kroesen, had worked there for twenty-five years and was often approached by people asking for his help in finding the betrayer of their relatives. Every time Vince or Pieter visited, there might be a new story; they were immensely valuable to the team because they gave a sense of the texture of life during the war.
Sometimes Kroesen was able to solve cases in short order, such as the case of the man who walked in one day wanting to know who had betrayed his parents. The man knew the address of their hiding place, so Kroesen simply checked who the official resident was at the time. It was a woman who had lived there with her nephew since the 1930s. Two months after the betrayal of the man’s parents, she moved to a bigger house—the house that had belonged to the people she betrayed. Meanwhile, the nephew changed his official address every two months, which was typical of collaborators who feared being tracked down by the resistance. Kroesen soon found the work records of the nephew. He’d been a student at the secret German spy school in Antwerp and had then worked for the SD as well as for the Einsatzstab Reichsleiter Rosenberg （ER）， the Nazi organization dedicated to appropriating cultural property. It was not difficult for Kroesen to conclude that it must have been the nephew who betrayed the man’s parents, who had no idea that they were being hidden by the aunt of a dedicated Dutch Nazi.
Once the Cold Case Team’s office in the north of Amsterdam was set up, visitors started to come. Perhaps most important for Thijs was the visit of the Dutch military’s chief rabbi, Military Police Colonel Menachem Sebbag. Thijs had met him through the commander of the Royal Navy barracks when he had been searching for a new office. On that occasion they had established an immediate rapport.
Thijs wanted to know what it would mean if the team actually found the betrayer of Anne Frank. Did the rabbi worry that they would stir up emotions they’d be better off avoiding? What if the betrayer were Jewish? Should the matter be left alone?
Rabbi Sebbag was very clear. “Hardly anything is of greater importance than the truth,” he said. “If the betrayer turned out to be Jewish, so be it.” The rabbi reminded Thijs that the Nazis had tried to dehumanize the Jewish people. “The truth,” he said, “is that Jewish people are human at all levels. As humans can or will betray each other, then there will also be Jewish people among them.”
In the office, the Cold Case Team kept a thick binder containing copies of the Kopgeld receipts that Vince had found at the National Archives in College Park, Maryland. Each of the 956 notes is forensic proof of payment of head money for the betrayal of one or more people. With bureaucratic precision, each is furnished with stamps, signatures, an amount in guilders, and the name of the recipient. Sometimes the names of the betrayed are mentioned, but other times only the number of betrayed men, women, and children is noted.
Rabbi Sebbag knew of the existence of Kopgeld but had never seen the receipts. When Thijs showed him the binder, he did not touch it. He stiffened. So many men, women, and children sentenced to death. Their absence was palpable in the profound sadness that filled the room.
20
The First Betrayal
Over the course of the investigation, various researchers worked on different scenarios and new information came in all the time. Vince saw the investigation as less chronological and more of an arc, which began with a betrayal far earlier than the 1944 call to the SD.
By the end of 1934, business at Opekta was picking up, and Otto rented larger offices at Singel 400. As is often the case with fledgling businesses, he found himself performing many roles, including salesman visiting housewives and wholesalers across the country. Business again improved in 1935 after Otto convinced a number of small wholesalers to stock pectin. He was finally able to employ more staff and hired a secretary, Isadora “Isa” Monas, and at least two product demonstrators.
One was a woman named Jetje Jansen-Bremer, whose job it was to attend various trade shows and explain the use of pectin. At the same time, Otto gave part-time jobs to Jetje’s husband, Josephus Marinue “Job” Jansen, and their eldest son, Martinus. Job built the wooden display cases, and Martinus helped with packaging and dispatch duties at the warehouse.