In spring 1973, we introduce the emergency numbers 110/112 in all local networks of the German Federal Post Office in what was then the administrative district of North Württemberg. However, the nationwide introduction fails - Siegfried Steiger then sues the state of Baden-Württemberg and the Federal Republic of Germany before the Stuttgart Administrative Court for the introduction of the emergency number (case reference: II 139/73). As expected, the lawsuit is rejected on 3 September 1973, but leads to broad public support.

The emergency numbers 110 for the police and 112 for the fire and rescue services had been in use in Germany since 1956, but only a few large cities had switched them on.