The Yokohama District Court on Oct. 28 gave a suspended 2 1/2-year prison term to a lieutenant commander of the Maritime Self-Defense Force for passing information on the U.S.-developed Aegis weapons system to another lieutenant commander, an instructor at an MSDF school in Etajima, Hiroshima Prefecture. Although the information, which included "special defense secrets," did not leak outside the MSDF, the court found him guilty of leaking defense secrets.

The trial was the first case to which public prosecutors applied the 1954 Law on Protection of Secrets for the Japan-U.S. Mutual Defense Assistance Agreement. The law covers not only members of the Self-Defense Forces but also ordinary citizens, and provides for imprisonment of up to 10 years for violators.

The passing of the sensitive data on the Aegis system, an advanced combat system to track and destroy enemy targets, has made the United States apprehensive over the possibility that the bilateral security treaty setup is being undermined. On the prosecution side, there was an opinion that the people involved could not be indicted since the case was a matter of information management within the MSDF. But the prosecution indicted the MSDF officer anyway apparently out of concern about the U.S.'s attitude. Criminal papers were filed with the prosecution against several other MSDF members, but the prosecution suspended indictment against them.