The court fight over President Obama's plan to shield 5 million immigrants from deportation involves complex legal issues. U.S. District Judge Andrew Hanen in Texas issued an order Monday temporarily blocking the program. Questions about the case:

Q: What would the administration's program do?

A: The program would "defer action" for a large class of immigrants currently in the country without legal authorization. They would not receive citizenship or legal status, but would not be at risk of deportation so long as the deferred action remained in effect.

Q: What legal authority does Obama claim?

A: The government has had some form of deferred action since at least the 1960s. Executive branch officials have argued — and courts have agreed — that the president and executive-branch agencies have significant discretion over which immigrants to deport. The legal justification is that the government has limited resources and that federal agencies can set priorities.

Q: What's the legal argument on the other side?

A: Discretion isn't unlimited. The government can't completely rewrite the law under the guise of setting priorities. The legal issue is whether Obama's program is so far-reaching that it goes beyond what can be justified as executive discretion. The plaintiffs in the case, 26 Republican-led states, have a strong case that the administration did go too far, the judge ruled.

Q: The Obama administration says the 26 states have no right to sue in this case. Why?

A: Federal courts only allow cases to proceed when the person or group bringing the case meets the legal standards for what is known as standing. To have standing, people or groups need to show that the action they want to challenge will have a direct impact on them. The administration argues that although GOP officials disapprove of Obama's decision, the states will not suffer any actual injury.

Q: What did the judge say?

A: Hanen ruled that the states would suffer an actual injury because the deferred-action program would cost them money. For example, states would probably be required to issue driver's licenses to immigrants with deferred-action status.

Q: Did the judge make a final ruling on the case?

A: No. Monday's ruling said that the states could take their claim to a full trial, which might not take place for months. In the meantime, the judge issued an injunction blocking the administration from starting the new programs.

Q: What happens now?

A: The government has said it will appeal. The case would go to the Fifth U.S. Circuit Court of Appeals, which could decide to leave Hanen's preliminary injunction in place until the judges of that court can hold a hearing. The appeals court could also dissolve the injunction.

Q: The judge said the administration may have failed to follow proper procedures. What's that about?

A: The federal government has a law that lays out the steps that agencies must take when they issue new rules. Those typically include notice and an extended period for public comment, often between 18 months and two years. The states argue that the Department of Homeland Security should have been required to follow those procedures in setting up the program.