Washington: Handing US President Barack Obama a partial victory in an election year, the Supreme Court Monday largely sided with his administration to strike down key parts of a controversial Arizona law on immigration.
But it was a less than complete win as the court`s 5-3 ruling also upheld the most controversial provision of the Republican-ruled state`s law involving police checks on people`s immigration status while enforcing other laws if "reasonable suspicion" exists that the person is in the US illegally.
"The national government has significant power to regulate immigration," Justice Anthony Kennedy wrote in the majority opinion, ruling the federal government had the power to block the Arizona law.
"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," he added.
In its ruling, the apex court also made clear the immigration status provision could still face future constitutional challenges depending on how the state enforces it.
The Obama administration had challenged four major provisions of the Arizona law that never were enforced, pending the legal ruling, arguing immigration matters were strictly a federal function.
Writing for the minority, Justice Antonin Scalia argued the court`s ruling encroached on Arizona`s sovereign powers.
"If securing its territory in this fashion is not within the power of Arizona, we should cease referring to it as a sovereign state," he wrote.
Provisions struck down included authorising police to arrest immigrants without warrant, making it a state crime for "unauthorized immigrants" to fail to carry identification papers and soliciting work or even indicating their willingness to do so with a "gesture or nod".
Arizona had passed the tough immigration law because of what it said was the federal government`s inability to stop the flow of illegal immigrants crossing from Mexico.
Similar laws passed by several other states are under challenge in lower courts in Georgia, Alabama, Utah, Indiana and South Carolina. Arizona`s appeal is the first to reach the Supreme Court.