This morning, the Supreme Court ruled on Arizona’s immigration law, striking down most parts, but allowing one of the most controversial. This appears to be a victory for those opposing the law, but the Supreme Court upheld the provision involving police checks on people’s immigration status while enforcing other laws. This decision will create significant discussion in the legal community, as this law, and the specific provision upheld are highly controversial.

Justice Anthony Kennedy authored the majority of the opinion in the 5-3 case. Kennedy acknowledged that “The national government has significant power to regulate immigration.” He added that “Arizona may have understandable frustrations with the problems caused by illegal immigration while that process continues, but the state may not pursue policies that undermined federal law.” Ultimately the majority recognized the balance between personal liberties and national security and state’s interests, and realized that Arizona’s legislation crossed the line.

The Court upheld the provision that allows police to check immigration status once they have stopped an individual legally, a stop that requires only “reasonable suspicion” after the Court’s ruling in Terry v. Ohio, and subsequent cases. This is potentially troubling, as the requirement for reasonable suspicion is rather low, and law enforcement officials have been accused of abusing “stop and frisk” laws. (See recent Stop Stop and Frisk march in Manhattan) The Court seemed to recognize this possibility and made clear that the immigration status provision could still face future constitutional challenges depending on how the state enforced it.

Justice Antonin Scalia, writing for the minority, argued the court’s ruling encroached on Arizona’s sovereign powers. He stated, “If securing its territory in this fashion is not within the power of Arizona, we should cease referring to it as a sovereign state.” This contrasts with the government’s position that immigration is a federal issue.

For those who oppose the law, this is clearly a victory for individual’s rights. For those who agreed with the law, it is a defeat. Yet the provision allowing police officials to inquire about immigration statuses based on reasonable suspicion will still give Arizona law enforcement a lot of leeway in policing against illegal immigrants. It will certainly be interesting to monitor that provision as it goes forward. Constitutionally, “reasonable suspicion” cannot be met by merely skin color, accents, or languages. But the line is not always clear, and the way Arizona implements this law will certainly be in the legal spotlight for years to come.