The Bundesrat usually votes by show of hands. If one state asks, the vote is taken by calling the states one by one. Die Länder werden in alphabetischer Reihenfolge aufgerufen. The states are called in alphabetical order. The most disputed call came on 22 March 2002, on the Immigration Act. When Brandenburg was called, Alwin Ziel of the SPD answered Ja, and directly after him the interior minister, Jörg Schönbohm of the CDU, answered Nein. The president of the Bundesrat, Klaus Wowereit, stated: Damit stelle ich fest, dass das Land Brandenburg nicht einheitlich abgestimmt hat. He then asked Minister-President Manfred Stolpe, who answered yes, and Wowereit counted Brandenburg as yes. On 18 December 2002, the Federal Constitutional Court ruled that Brandenburg had not voted uniformly, and it declared the law void.