The pros and cons of changing the Constitution were on full display Sunday — the 62nd Constitution Day — with both opponents and proponents holding rallies to push their causes.

With a national referendum law taking effect next year to set the procedures for constitutional amendments, several groups in favor of change underlined the need to revise the Constitution.

"There is a huge gap between reality and the Constitution that remains the same since it took effect 62 years ago," Junpei Kiyohara, a representative of a Tokyo-based revisionist group founded by the late former Prime Minister Nobusuke Kishi, told a forum in the capital.