After a former university professor’s early February arrest in Osaka for stolen credit card use, it quickly came to light that prosecuting neither that charge, nor the insurance fraud leading to the arrest, were the Japanese police’s end game.

The professor, it was revealed, had been working for North Korea, including activities that made money for the regime, and Japan, lacking South Korea’s legal tools for combating pro-Pyongyang espionage, had needed other means to stop him.