The credibility of the nation's defense administration is at stake in the wake of a fresh scandal embroiling a former top bureaucrat of the Defense Ministry and a defense contractor. We welcome the nonpartisan decision, reached at a Lower House select committee last week, to summon former administrative Vice Defense Minister Takemasa Moriya to the Diet as a sworn witness on Monday.

The 63-year-old Mr. Moriya, who just retired from the ministry two months ago after having served as its administrative chieftain for four years, is under fire over his allegedly dubious relations with defense equipment trader Yamada Corp.

According to media reports, he frequently played golf with a then senior executive of the contractor, and was wined, dined and entertained on the executive's tin, in possible violation of the Self-Defense Forces ethics code enforced in 2000. Another allegation is that Mr. Moriya possibly influenced the Air Self-Defense Force's choice of engines for the next-generation CX transport aircraft. The deal went to General Electric Co. of the United States, whose sales agent in Japan is the trading firm set up by the former Yamada executive last year.