The Supreme Soviet was composed of two chambers, each with equal legislative powers, with members elected for four-year terms:
The Soviet of the Union, elected on the basis of population with one deputy for every 300,000 people in the Soviet federation.
The Soviet of Nationalities, represented the ethnic populations as units, with members elected on the basis of 32 deputies from each union republic, 11 from each autonomous republic, five from each autonomous oblast, and one from each autonomous okrug. The administrative units of the same type would send the same number of members regardless of their size or population.
By the Soviet constitutions of 1936 and 1977, the Supreme Soviet was defined as the highest organ of state power in the Soviet Union, and was imbued with great lawmaking powers. In practice, however, it did little more than approve decisions made already by the USSR's executive organs and the Communist Party of the Soviet Union. This was in accordance with the Communist Party's principle of democratic centralism, and became the norm for other Communist legislatures. The Supreme Soviet convened twice a year, usually for less than a week. For the rest of the year, the Presidium performed its ordinary functions. Often, the CPSU bypassed the Supreme Soviet altogether and had major laws enacted as Presidium decrees. Nominally, if such decrees were not ratified by the Supreme Soviet at its next session, they were considered revoked. In practice, however, the principle of democratic centralism rendered the process of ratifying Presidium decrees a mere formality. In some cases, even this formality was not observed. After 1989 it consisted of 542 deputies. The meetings of the body were also more frequent, from six to eight months a year. Between 1938 and February 1990, more than 50 years, only 80 laws were passed by the Supreme Soviet, less than 1% of total legislative acts.
New composition 1991, unlike previous convocations, there were no elections for the new composition of the Supreme Council instead members of the council were delegated from the council of union republics that continued to be members of the Soviet Union.
Beside the Supreme Council, in the Soviet Union supreme councils also existed in each of the union and autonomous republics. The supreme councils of republican level also had presidiums, but all those councils consisted of one chamber. After the dissolution of the Soviet Union, some councils of the succeeded independent republics simply changed their name to their more historic name or to emphasise the importance of the council as a national parliament, while others changed to double-chamber assemblies. All republics in the USSR were soviet, yet 15 were of union level, while the other, autonomous republics, were subordinated to the union republics.
