The Upper House on Monday enacted a law that establishes procedures for a national referendum to revise the Constitution. The legislation was backed by the Liberal Democratic Party, Komeito, one member of the opposition Democratic Party of Japan and an independent. The law's provisions concern the most important process in Japanese politics. But its contents raise many questions and may cause confusion and raise objections when a referendum process is set into motion.

The biggest question concerns the fact that the law fails to mandate a minimum turnout rate for a referendum to be considered valid. The law merely states that a revision will become effective if it is favored by a majority of valid votes in a referendum. Thus if turnout for a referendum is 50 percent, theoretically a 25 percent vote would be enough to revise the nation's basic law. A situation in which a relatively small number of people decides the shape of the nation's supreme law would run counter to the constitutional principle that sovereign power resides with the people.

Article 96 of the Constitution stipulates that amendments to the Constitution shall be initiated through a concurring vote of two-third or more of all the members of each House of the Diet. Under the new law, the minimum number of lawmakers in each House necessary for submitting a bill for a constitutional revision is 100 in the Lower House and 50 in the Upper House.