Sweden’s Former Security Adviser Convicted After Leaving Secret Documents Behind

Sweden’s former national security adviser, Henrik Landerholm, was convicted on October 19, 2026, of negligently handling secret information. The Svea Court of Appeal in Stockholm overturned his acquittal and imposed 80 daily fines of 650 Swedish kronor, totaling 52,000 kronor.

The case began at Gällöfsta, a conference center north of Stockholm, in March 2023. Landerholm brought secret documents with him and locked them in a safe. When he checked out the following day, he left the papers behind. They were later discovered in the safe, which was then unlocked.

That gave unauthorized people access to information whose disclosure to a foreign power could harm Sweden. Even when acquitting Landerholm on September 5, 2025, the Attunda District Court found that secret information had been exposed. Whether anyone actually read the contents remained unproven.

The decisive question was the seriousness of his negligence. The district court considered his conduct negligent. The appeals court found it amounted to gross negligence, the threshold required for criminal liability in this case.

His position and experience were central to that finding. Landerholm had held senior government posts for many years and had described himself as highly experienced in handling secret information. The appeals court concluded that substantial carelessness when emptying the safe was the only reasonable explanation for leaving the documents behind.

His responsibilities reached the center of government. Sweden’s then-prime minister, Ulf Kristersson, appointed Landerholm as the country’s first national security adviser in November 2022. His initial task was to establish a function within the prime minister’s office to coordinate national security policy and analysis. He had previously served as an army officer, ambassador and head of the Swedish Defence University.

The documents reportedly concerned a particularly sensitive diplomatic effort. According to findings by Swedish newspaper Dagens Nyheter, subsequently reported by public broadcaster SVT, the material included Sweden’s strategy for securing Turkey’s approval of its membership in the North Atlantic Treaty Organization, or NATO.

At least one document reportedly contained information from a meeting between Landerholm and the United States’ then-national security adviser, Jake Sullivan. Those details come from media reporting; the court’s public statement describes the material in general terms as secret, security-sensitive information.

The incident occurred while Sweden was still seeking admission to the alliance. It became a NATO member on March 7, 2024.

Landerholm stepped down in January 2025 after the investigation began. He maintains his innocence and described the conviction as disappointing. He and his defense lawyer, Johan Eriksson, will review the judgment before deciding whether to appeal to Sweden’s Supreme Court.