For the first time, in 2013 the electoral law introduced adjustment seats to compensate for surplus seats at the federal level . For the last two elections, this led to a considerable increase of the Bundestag's size . The reform debate to shrink the Bundestag back to its original size of 598 seats that began in 2013, came to a preliminary end when in October 2020 the new electoral law was passed by the Grand Coalition . The law includes three mechanisms to contain the Bundestag's size: First, half of the list mandates of the party that has surplus seats can be used for the compensation of surplus seats . Second, up to three surplus seats can be left untouched by adjustment seats . Third, the number of constituencies is reduced from 299 to 280 . Simulations demonstrate that these mechanisms most likely will not be sufficient to prevent a considerable augmentation of the Bundestag . Furthermore, the new law includes elements which could prove to be unconstitutional .
The reform of the electoral law in 2013 introduced adjustment seats that compensate for surplus mandates, resulting in the Bundestag increasing in size . The new electoral law passed by the Grand Coalition in October 2020 will not provide an effective cure to this problem . The "usual suspects" that have been proposed as possible remedies, especially reducing the number of constituencies, but also accounting for list mandates with surplus mandates and capping "excess" direct mandates, all imply problematic effects . Against this background, forms of rank‑oriented personalized proportional electoral systems, which adhere to the logic of Baden‑Wuerttemberg's state electoral system, seem to be promising reform perspectives . They preserve the element of the personal vote and could even strengthen this . Not only can they guarantee that the Bundestag will not exceed its regular size, but they also secure proportionality between the parties at the federal level as well as proportionality between the several state lists of one party .
Following a long lasting debate about the electoral law, the new electoral law of the Federal Republic of Germany was passed on May 3rd 2013 which contains as an important element adjustment seats. The starting point of the debate was a judgment of the German Supreme Court in 2008 which had declared the phenomenon of the so called negative voting weight unconstitutional. Every future reform of the electoral system will be evaluated according to the extent it contains a solution of this problem. In order to evaluate which institutional arrangements are permissible, an argument is made which forms of negative voting weight have to be judged as normatively problematic and which forms can be considered as harmless. Adapted from the source document.