Facts
In the Canton of Aargau, a popular vote on May 18, 2003 approved the reduction of the Grand Council from 200 to 140 members. Subsequently, the canton amended the relevant provisions in the Cantonal Constitution (§§ 76 para. 2 and 77 para. 2). The Cantonal Government proposed to the Grand Council to combine the districts into constituency associations in order to avoid high natural thresholds in small constituencies. However, the Grand Council decided in the second reading to refrain from creating constituency associations.
The Green Party of Aargau and other parties then filed voting rights complaints against the new Grand Council Election Act. They argued that the waiver of constituency associations would lead to unconstitutional natural thresholds and thus violate the voting rights of the electorate.
Considerations
The Federal Supreme Court states that the system of proportional representation according to § 77 para. 1 of the Cantonal Constitution requires that the canton is either divided into the largest possible and equal constituencies or not divided at all. The smaller a constituency is, the higher the natural threshold, i.e., the vote share a list needs to obtain a seat.
The constitutional provision in § 77 para. 2 sentence 2 of the Cantonal Constitution, which allows the formation of constituency associations, is to be understood in such a way that the legislator is obliged to create such associations if this is necessary to avoid disproportionate thresholds. The waiver of constituency associations thus contradicts the purpose and intent of the constitutional provision.
The Federal Supreme Court considers natural thresholds of over 10% as…