The Supreme Court has rejected an appeal filed by a U.S. health-food maker against a high court decision that upheld a reporter's right to keep a news source secret. The decision concerns an NHK report that the Japanese subsidiary of the company had underreported its revenues to reduce tax bills.

The significance of the latest decision is in the Supreme Court's declaration that keeping a news source secret is a necessary means of ensuring freedom of news coverage and thus has "important social value." It noted that freedom of news coverage (and other forms of expression) is guaranteed by Article 21 of the Constitution. It said news reports provide material for people living in a democracy to form political opinions and thus serve to enhance people's right to know. News sources were deemed to fall under the category of occupational secrets.

For the first time, the Supreme Court set down conditions under which a reporter may refuse to disclose his or her news sources: The reporting concerns the public interest; the news-gathering method does not violate laws that provide penalties; the civil lawsuit in question has social significance; and disclosure of the news source's identity is not indispensable.