Germany has on the federal level a bicameral legislature. The parliament has two chambers. The Bundestag (Federal Diet) nominally has 598 members, elected for a four year term, 299 members elected in single-seat constituencies according to first-past-the-post, while a further 299 members are allocated from statewide party lists to achieve a proportional distribution in the legislature, conducted according to a system of mixed member proportional representation. Voters vote once for a constituency representative, and a second time for a party, and the lists are used to make the party balances match the distribution of second votes. In the current parliament there are 16 overhang seats, giving a total of 614. This is caused by larger parties winning additional single-member districts above the totals determined by their proportional party vote. A party must receive 5% of the national vote or win least three directly elected seats to be represented in the Bundestag. This rule, often called the "five percent hurdle", was incorporated into Germany's Election law to prevent political fragmentation and strong minor parties, which was considered a major reason for the inefficacy of the Weimar Republic's Reichstag. The first Bundestag elections were held in the Federal Republic of Germany ("West Germany") on August 14, 1949. Following Reunification, elections for the first all-German Bundestag were held on December 2, 1990. The last election was held on September 18, 2005, the new (16th) Bundestag convened on October 18, 2005. The number of Bundestag Deputies was reduced from 656 to 598 beginning in 2002, although under the additional member system, more deputies may be admitted if a party wins more directly elected seats than it would be entitled to under proportional representation.
The Bundesrat (Federal Council) is the representation of the state governments at the federal level. It consists of 69 members who are delegates of the 16 Bundesländer and usually, but not necessarily include the 16 Minister Presidents themselves. The Länder each have from three to six votes in the Bundesrat, dependent on population. Bundesrat members receive voting instructions from their state governments.
The legislature has powers of exclusive jurisdiction and concurrent jurisdiction with the Länder in areas specifically enumerated by the Basic Law. The Bundestag bears the major responsibility. The necessity for the Bundesrat to concur on legislation is limited to bills related to revenue shared by the federal and state governments and those imposing responsibilities on the states, although in practice, this means that Bundesrat concurrence is very often required.
Since the political orientation of the Bundesrat (which depends on the various state elections that occur independently of the federal ones) is quite frequently the opposite of that of the Bundestag, it has, in recent years, become more and more of a forum for the opposition parties, as opposed to one for state interests, as the constitution intended.