Japanese society values diplomas -- even if not as much as before. This may be part of the reason why Mr. Junichiro Koga, an up-and-coming Lower House member of the Democratic Party of Japan, made false claims about his educational background in November's general election. The scandal broke about a week ago, when Mr. Koga claimed that he had graduated from Pepperdine University in California. But the school announced that it never issued him a diploma. Mr. Koga visited the United States to get the record straight -- but to no avail.

On Tuesday, Mr. Koga acknowledged that he had failed to earn the credits required for graduation. He admitted the mistake and tendered his resignation to the party, but vowed to carry on as an independent member of the Diet.

At a special meeting of executive officials on Thursday, however, the DPJ decided to reject his resignation from the party; instead, it struck Mr. Koga's name from the party roll. As the heaviest punitive step under the party's code of ethics, the decision is almost equal to a call on Mr. Koga to quit the Diet.