Tuesday’s passage by the Lower House of a bill to amend the national referendum law in relation to constitutional revision puts the spotlight on a powerful Diet group tasked with debating the controversial issue. The bill is expected to be sent to the Upper House this week and become law by next month.

The revisions would entail an increase in the number of polling stations, allowing people to cast their ballots at railway stations and commercial facilities. It also includes a mandate for enacting legislative restrictions within three years on the amount of money that can be spent on referendum-related television, radio and internet advertising.

While an actual referendum on constitutional changes will not be held anytime soon, constitutional revision is likely to be a major campaign issue in the next Lower House election. But any revisions eventually presented in a referendum would have to be agreed to first by the Commission on the Constitution, before then being sent to the Diet at large.