Swiss Banking Code

The Swiss Banking Code is Switzerland’s response to the Gestapo’s systematic attempts to uncover German-held accounts: it made banks’ disclosure of clients’ holdings punishable by imprisonment. The novel presents the code not as an absolute refuge but as one stage in a contest between secrecy and surveillance, followed by account arrangements that reduced banks’ direct involvement without eliminating the danger that state agents could gain access.

Origins in the Gestapo’s campaign

In 1934, Reinhard Heydrich sent Gestapo agent Georg Hannes Thomae to Switzerland to identify German account holders. Thomae established himself in Zürich, cultivated relationships with female bank cashiers and minor bank officials, and posed as an intermediary when the Gestapo suspected someone had an illegal account. If a bank accepted his deposit, the Gestapo treated that as confirmation that the account existed. Its holder could then be arrested and tortured to obtain the account’s details, after which the bank received a formal cable requesting the return of the assets.

The campaign extended beyond individual deception. German communications with Switzerland were routinely intercepted, and clients faced execution or imprisonment in concentration camps. The combination of infiltration, communications monitoring, and coercion made ordinary banking secrecy inadequate: the banks’ dealings could become an information channel for the German police.

Legal protection and its limits

In response to public outrage, the Swiss National Assembly rushed through a new banking code. It prohibited banks from disclosing details of clients’ holdings and attached imprisonment as the penalty. Thomae was exposed and expelled. The measure established a legal prohibition against the disclosure that the Gestapo had sought to compel, while making clear that such protection had been introduced in direct response to an organized campaign of surveillance and pressure.

The law did not restore ordinary cross-border banking. Swiss banks considered German business too dangerous and burdensome; communication with clients had become nearly impossible, and respectable bankers were reluctant to take part in transactions with life-or-death consequences. By 1939, the once-profitable German numbered-account business had collapsed, while hundreds of accounts had been abandoned by owners too frightened to claim them. The code offered a formal safeguard, but it could not by itself make the German state’s reach disappear or make owners able to communicate safely with their banks.

Numbered deposits and the code’s vulnerability

After 1939, the demand to move property out of Germany rose sharply. Banks such as Zaugg developed a different deposit arrangement: for a fee of 200 francs, a customer received a box and number, a key, and an authorization letter. Possession of the key and letter allowed the holder to claim the contents without questions. Multiple keys and authorization letters could be issued, so access could pass to another person, including an heir, without requiring the bank to manage the transfer directly.

That design also exposed the limit of secrecy. If the Gestapo obtained the letter and key, the bank could hand over the assets without publicly disclosing client information or formally breaking the banking code. The arrangement thus shifted practical control toward whoever held the access documents: it reduced the bank’s role in the transaction, but did not protect the contents against someone who acquired the necessary credentials.

Afterlife in the investigation

The Swiss government banned these accounts at the end of the war under pressure from Berlin and allowed no new ones, but existing accounts remained valid under their original terms. Their continued existence made them valuable and transferable. In the investigation, Stuckart’s matching arrangement links the numbered-account system to the movement and concealment of assets, while March’s inquiries into Swiss banking are set against a wider pattern of state surveillance: a clandestine recording device captures Martin Luther’s call, and a wiretap later reveals that Globus knew Luther’s intended meeting through intercepted communications.

The code therefore matters both as a concrete legal response to Gestapo methods and as part of the novel’s contrast between formal privacy and practical control. Swiss law could forbid disclosure and punish a bank for it; it could not guarantee that account holders remained beyond the reach of coercive power, or that valuable assets hidden behind secrecy had been acquired legitimately.