The law (passed in August 2006) was designed to punish landlords and employers accused of renting to or hiring anyone the city deems an "illegal alien." The ACLU challenged that law in district court and won in 2007. Today's Third Circuit Decision was a response to an appeal by the city of Hazleton.
This decision is especially important in light of the recent proliferation of anti-immigrant sentiment and laws around the country (most noteably, Arizona's SB1070). Today's unanimous opinion, based on the Supremacy Clause, explains that courts must intervene where "states and localities directly undermine the federal objectives embodied in statutes enacted by Congress." The Hazleton law, the court said, was in direct conflict with Congressional intent and therefore, cannot stand.
In a statement today, Omar Jadwat, ACLU Immigrants' Rights Project staff attorney and one of the attorneys who argued the case, called the decision "a major defeat for the misguided, divisive and expensive anti-immigrant strategy that Hazleton has tried to export to the rest of the country."