Reich leadership had to follow. The Reichsrat had the right to advise on and to veto legislation, but the Reichstag could override a veto and was thus nominally the stronger of the two parliamentary bodies. Since the Reichstag had many parties and it was not easy to unify two-thirds of the votes, the governing parties in the Reichstag usually tried to reach an agreement with the Reichsrat in advance. The fact that the chairman of the Reichsrat was a member of the Reich government also curtailed the Reichsrat's sovereign rights: it could be convened only if one third of its members requested it of the Reich government (Article 64). Because the chairman of the Reichsrat was a government minister, the Reich also had a determining influence on the course of the Reichrat's business. The Reichsrat was not a purely legislative body. Since it was required to approve the majority of governmental acts (), it also participated in the administration of the Reich. As a result, the states, supported by the expertise of their ministerial bureaucracies, were able to exert considerable influence on the implementation of Reich laws, which they also usually executed on their own authority. Due to the relative stability of the state governments, the Reichsrat was seen as one of the last firm anchors of Weimar institutions, especially in the final phase of the Republic when the Reichstag was increasingly unable to act. The weakening of the Reichsrat in comparison to its position under the constitution of the German Empire is part of the generally more centralized nature of the Weimar Constitution, which significantly expanded the Reich's legislative authority and its supervisory rights over the states. The "sovereignty of the Reich over the states" that was then assumed in constitutional law, together with Finance Minister Matthias Erzberger's reforms of 1919/20 which introduced a national income tax, led to a significant weakening of the position of the constituent states that was not reversed until the constitution of the Federal Republic of Germany came into force in 1949. Its Bundesrat is modeled on the Reichsrat in its composition and competencies. Compared to the Reichsrat, the Bundesrat of the Federal Republic has a stronger position with regard to laws that require its approval (), over which it has an absolute right of veto, but a weaker one with regard to laws that do not (). The Bundesrat can veto them, but