If constitutional revision is proposed at a Diet session in the future, a referendum exclusively for the revision is likely to be conducted separately from a national election, several Liberal Democratic Party lawmakers have disclosed. The next House of Representatives election will be held in December 2018 at the latest, and the next House of Councillors election will be in the summer of 2019. The Deliberative Council on the Constitution in each chamber of the Diet has just begun summarizing the points under discussion. It remains to be seen when the council will be able to decide which articles should be revised. Given the current situation, a referendum for constitutional revision will not be held until after the Tokyo Olympics and Paralympics in 2020.

Since taking office, Prime Minister Shinzo Abe has been expressing his intention to revise the Constitution. He will likely extend his term by three years in the next LDP presidential election to be held in September 2018. After that, Abe will probably gauge the best timing for conducting a referendum for constitutional revision.

Article 96 of the Constitution stipulates that a referendum must be implemented either separately or simultaneously with a national election. However, both ruling and opposition party members of the House of Representatives Research Commission on the Constitution established in 2000 (chaired by Taro Nakayama) agreed that a referendum should not be held at the same time as a national election. This is because the lawmakers agreed that there are significant differences between a national election and a referendum for the constitutional revision. While lawmakers compete to take the reins of the government in a national election, a referendum is solely to decide whether the Constitution should be revised. Although national elections are restricted by a number of regulations, referendums should be in principle free from regulations. The lawmakers concerned have decided that it would be difficult to reconcile these differences between the two. (Abridged)