The House of Representatives, the lower chamber of the Diet, passed an active cyber defense bill on Tuesday and sent it to the House of Councilors, the upper chamber.

The bill was supported by both the ruling Liberal Democratic Party and the main opposition Constitutional Democratic Party of Japan after being revised to respect the secrecy of communications, which is guaranteed by the Constitution.

The bill is expected to be enacted by the end of the current ordinary Diet session, with the government planning to fully introduce an active cyber defense system in 2027.

According to the bill, the government would collect and analyze data on communications between foreign countries and between Japan and other countries, even in peacetime. If it detects signs of impending major cyberattacks, police and the Self-Defense Forces would take steps to neutralize threats, such as deleting hostile programs in potential perpetrators' servers.

In consideration of personal privacy, the government would monitor only technical information such as internet protocol addresses and character strings of attack commands, excluding the "substantive content" of communications such as the body of emails.

The government would set up a committee under the Cabinet Office to oversee active cyber defense operations. Government employees could be jailed for up to four years or fined up to ¥2 million ($13,500) for mishandling related data.

The revised bill was jointly submitted by the LDP, the CDP, Nippon Ishin no Kai, the Democratic Party for the People, LDP coalition partner Komeito and a group called Yushi no Kai.

It includes a new clause stating that the secrecy of communications must not be unreasonably restricted and a supplementary provision that calls for the active cyber defense system to be reviewed after three years.