The 2009 general House of Representatives election was the first unconstitutional lower house election under the current electoral system introduced in 1994 (parallel voting and "small" FPTP single-member electoral districts/"Kakumander"). In March 2011, the Grand Bench ("daihōtei") of the Supreme Court ruled that the maximum discrepancy of 2.30 in voting weight between the Kōchi 3 and Chiba 4 constituencies in the 2009 election was in violation of the constitutionally guaranteed equality of all voters. As in previous such rulings on unconstitutional elections (1972, 1980, 1983 and 1990 Representatives elections, 1992 Councillors election), the election is not invalidated, but the imbalance has to be corrected by the Diet through redistricting and/or reapportionment of seats between prefectures.