In the 1963 case of Germano et al. v. Kerner, Governor of Illinois, et al., a group of voters in Cook County, Illinois challenged the constitutionality of an apportionment law that had been passed by the state legislature in 1955. The plaintiffs argued that this law violated their rights under the Equal Protection Clause because it resulted in unequal representation for urban and rural areas within legislative districts. They claimed that due to population growth and shifts since 1901 (the last time district boundaries were redrawn), some districts now had significantly more residents than others - yet each still elected only one representative to the state senate or house. The Supreme Court agreed with these arguments and ruled unanimously against Governor Otto Kerner Jr., declaring Illinois' existing apportionment scheme unconstitutional as it diluted votes from densely populated areas like Chicago compared to those from less-populated rural regions – violating "one person, one vote" principle enshrined in Fourteenth Amendment's Equal Protection Clause. This decision was part of a series during early-1960s where SCOTUS mandated equal representation for all citizens across states; setting precedent for future redistricting cases ensuring fairer political representation nationwide.

In the dissenting opinion for Germano et al. v. Kerner, Governor of Illinois, et al., Justice Harlan argued that the Court should not have intervened in this case as it involved a political question rather than a judicial one. He believed that issues regarding legislative apportionment and district boundaries were matters best left to state legislatures and Congress to resolve, not federal courts. Furthermore, he contended that there was no clear constitutional violation or standard by which to judge fairness in representation; thus making it inappropriate for the judiciary branch to interfere with these inherently political decisions made by elected officials who are accountable directly to voters. The justice also expressed concern about potential consequences of such intervention on future cases involving similar issues.