By throwing out most of the anti-Latino Arizona immigration law and neutering the rest, the Supreme Court struck a rare blow for fairness and justice on Monday. Let’s hope this is the beginning of a streak.

Let’s also hope that Chief Justice John G. Roberts Jr., who sided with the 5 to 3 majority in this case, likes the view from the liberals’ end of the bench. They could use his vote on the health-care-reform ruling, expected to be announced Thursday.

In a perfect world, the court would have definitively eliminated the most notorious section of the Arizona law: the requirement that police check the immigration status of anyone who is detained. Because of its chilling invocation of police-state tactics, this became known as the “papers, please” provision.

The court ruled that it is too soon to invalidate this part of the law but significantly narrowed the measure’s scope — and practically dared Arizona officials to step out of line. “This opinion does not foreclose other preemption and constitutional challenges to the law as interpreted and applied after it goes into effect,” the court wrote. Translation: We’ll be watching closely.