Bill to amend law on Japanese Constitution revision poll likely to pass Diet May 6, 2021 (Mainichi Japan) Senior lawmakers of the ruling Liberal Democratic Party and the main opposition Constitutional Democratic Party of Japan attend a meeting over a bill to amend the national referendum law on revision of the Constitution in parliament in Tokyo on May 6, 2021. (Kyodo) TOKYO (Kyodo) -- A bill to amend the national referendum law on revision of the Constitution is likely to pass parliament by the end of the current session through mid-June, as the pro-revision ruling party agreed Thursday to accept the opposition force's request to tweak it.