However, in the case of treaties, the budget, and the selection of the prime minister, the House of Councillors can only delay passage, but not block the legislation.

Parties who vote with the government in the Diet, but are not part of the cabinet (e.g. SDP & NPH after the 1996 election) are not shaded.

Both houses, and also the Emperor, had to agree on legislation, and even at the height of party-based constitutional government, the House of Peers could simply vote down bills deemed too liberal by the Meiji oligarchy, such as the introduction of women's suffrage, increases in local autonomy, or trade union rights.

However, the right to vote on, and if necessary to block, legislation including the budget, gave the House of Representatives leverage to force the government into negotiations.

[14] During the Taishō political crisis in 1913, a no-confidence vote[15] against the third Katsura government, accompanied by major demonstrations outside the Diet, was followed shortly by resignation.

In the same year, the Rice Riots had confronted the government with an unprecedented scale of domestic unrest, and a German Revolution brought the Prusso-German monarchy to an end, the very system Meiji oligarchs had used as the main model for the Meiji constitution to consolidate and preserve Imperial power.

However, the balance of powers between the two houses and the influential role of extra-constitutional actors such as the Genrō (who still selected the prime minister) or the military (that had brought down several cabinets) remained in essence untouched.

In the 1946 election to the House of Representatives, held under the U.S.-led Allied occupation of Japan, women's suffrage was introduced, and a system of "large" electoral districts (one or two per prefecture) with limited voting was used.

Since the end of US rule in 1952, it has been the norm that the prime minister dissolves the House of Representatives before its 4-year term expires.

[18] In 1955, prime minister Ichirō Hatoyama oversaw the creation of the Liberal Democratic Party (LDP), which since his third government has dominated Japanese politics under the 1955 System.

Hatoyama planned to change the electoral system to first past the post, introducing a bill to that effect in March 1956.

Electoral reform came into vogue again in the 1970s, but Kakuei Tanaka's plan met opposition internally in the LDP and never came to a vote in either chamber of the Diet.

Japan entered a lengthy recession in the 1990s (see Lost Decades), which many people blamed on the LDP.

As with party colleagues Ichirō Hatoyama and Kakuei Tanaka before him, prime minister Toshiki Kaifu of the LDP unsuccessfully tried to reform the electoral system in 1991.

However, the Morihiro Hosokawa government got the 1994 Japanese electoral reform through the Diet, introducing a parallel voting system which went into effect at the next election in 1996.

Prime minister Junichiro Koizumi introduced a bill to the House of Representatives in 2006 on changing the Imperial Household Law to allow a woman to ascend the Chrysanthemum Throne (see Japanese imperial succession debate), but he withdrew the bill after the birth of Prince Hisahito of Akishino the same year.