Twenty-six states have sued the Obama administration for making regulations that directly contradict law and inflict taxpayers with millions of dollars in costs for illegal immigrants.

On Tuesday, the Supreme Court agreed to hear argument in United States v. Texas, the case in which 26 states are challenging the Obama administration’s authority to grant temporary lawful presence for up to 5.5 million illegal aliens.

This will be one of the biggest cases of the Supreme Court term ending in June, both for its legal and political outcomes. Here is what you need to know.

At the most basic level, this case is about stopping yet another President Obama end-run around Congress. In accordance with its constitutional authority, Congress has established an elaborate immigration scheme governing which aliens may enter the United States, how long they may stay, and which aliens must be removed. Obama and the Democrats do not like Congress’ immigration scheme, but they lack the votes to change it.

Obama’s solution to his immigration proposals’ lack of popularity was to simply ignore Congress. On November 20, 2014, at Obama’s direction, Department of Homeland Security (DHS) Secretary Jeh Johnson issued a memo purporting to lay out a new form of immigration relief called Deferred Action For Parents of Americans, also known by its acronym, “DAPA.”

Legalizing and Subsidizing Anchor Babies

Under DAPA, certain aliens unlawfully present in the United States could obtain temporary lawful status if, among other things, they have a child who is a U.S. citizen or a lawful permanent resident. In other words, for the first time, the Obama administration brought the “anchor baby” concept into practice in the United States.

These two statuses come with a host of federal and state benefits.

Under the DAPA program, a successful alien applicant gets two things from DHS: “deferred action,” which confers temporary lawful status, and work authorization. But these two statuses come with a host of other federal and state benefits, including Social Security retirement benefits, Social Security disability benefits, Medicare, the Earned Income Tax Credit, state driver’s licenses, and state unemployment insurance. Setting aside the federal costs, the states (or, rather, the states’ hardworking taxpayers) would end up paying millions of dollars because of DAPA.

So Texas and 25 partner states promptly sued to block this plan. The preliminary injunction hearing before the district court took place on January 9, 2015. We’re barely past one year later, and already the Supreme Court has agreed to resolve the case. That is an extraordinarily fast pace for a very complicated case. Legally, there are four moving pieces to this, and any one of them could be the deciding issue.

Opposition Based on Procedure and Substance

The states’ argument is goes to the heart of the matter. First, Obama and Johnson cannot simply will into existence new federal programs at any time they choose. Congress, in the Administrative Procedures Act (APA), required federal agencies to use what is called notice-and-comment rule-making when they promulgate new substantive rules.

Obama and Johnson cannot simply will into existence new federal programs at any time they choose.

Put another way, the executive branch can’t announce new programs of its own devising without first asking the American public for comment and then responding to those comments. Johnson did not utilize notice-and-comment rule-making before creating DAPA, so his memo directing DHS to create DAPA violates the law. This is what is known as the states’ procedural APA claim, and it is the basis of the district court’s ruling in the case.

Second, the states also have a substantive APA claim. This argument, which persuaded the Fifth Circuit Court of Appeals, is that Congress never authorized DHS to create DAPA in the first place. So, whether DAPA requires notice-and-comment or not, DHS cannot create the program.

This too is indisputably true. The Immigration and Nationality Act (INA) creates several forms of immigration relief, including temporary statuses, and when it does, it does so by name. For example, asylum, adjustment of status, cancellation of removal, the visa provisions, waivers, and conditional statuses are all explicitly provided for in voluminous statutory text.

INA is a fractal monstrosity decades in the making and unmaking, but DAPA is not in there. Nor is the Obama administration’s newfound authority to grant work authorization to anyone it chooses. Congress specifically prescribed the groups to whom work authorization should be given. DAPA recipients are not one of them.

A Constitutional Question Over the President’s Job Description

Third, the states are making a substantive constitutional argument under the Take Care Clause. This claim deserves special note because neither the district court nor the Fifth Circuit found it necessary to rule on it, but the Supreme Court ordered the states and the federal government to brief it anyway. This idea is that by ignoring the expressed will of Congress, DAPA violates the constitutional command that the executive branch “shall take care that the laws be faithfully executed.”

DAPA violates the constitutional command that the executive branch ‘shall take care that the laws be faithfully executed.’

Over the years, the courts have been loath to resolve Take Care Clause challenges, but if the liberal wing of the high court resolves the statutory challenges in the federal government’s favor, it will have no choice but to address the constitutional challenge.

The states’ Take Care claim goes like this: not only is DAPA not authorized by Congress (that’s the substantive APA challenge discussed above), DAPA is in fact directly contrary to the expressed will of Congress. Congress explicitly provided that a U.S. citizen (or lawful permanent resident) child of an illegal alien could not be the basis for legalizing an alien parent’s immigration status until the child turned 21 years of age unless, among other things, the removal of the parent would cause exceptional and extremely unusual hardship to the child.

Congress wanted it to be quite difficult for aliens to leverage U.S.-born children into lawful immigration status. DAPA ignores this policy goal and grants lawful status regardless of the age and hardship restrictions established by Congress in violation of the executive branch duty to take care that the laws of Congress be faithfully executed.

Just Change Your Laws and There’s No Problem

For its part, the Obama administration’s major defense is that it need not have a defense on the merits. The administration has mustered only half-baked theories (not to mention outright debunked claims) in response to the states’ procedural and substantive arguments. Instead, the administration argues that the states do not have standing to challenge the DAPA program in court.

The Obama administration’s major defense is that it need not have a defense on the merits.

Its theory is that Texas (as well as the other states) is not harmed because Texas need only change its laws that provide driver’s licenses, unemployment insurance, and other things for people who the federal government deem lawfully present. That way, the federal government argues, Texas can avoid the cost of paying for the freshly legalized DAPA recipients.

But this argument goes too far. It was not Texas’ preexisting laws that altered the status quo; it was the Obama administration’s unilateral and unlawful implementation of a new immigration relief for illegal aliens that gave rise to Texas’ injury. Moreover, the Obama administration just won a lawsuit it brought against Arizona when that state tried to deny driver’s licenses to the newfound beneficiaries of Obama’s immigration largess.

Prime Presidential Election Positioning

Do not be misled by the claims of Obama and the Democrats that he was forced to act because Congress would not. This is not an area in which Congress had been silent. To the contrary, Congress’ immigration scheme is comprehensive. Even though Congress delegated authority to DHS to administer specific forms of immigration relief, it did not leave room for the agency to create new forms of immigration relief. That is Congress’ role alone, and by usurping that role, the Obama administration violated its statutory and constitutional duties.

The Obama administration violated its statutory and constitutional duties.

This case is also not about a government policy of prosecutorial discretion versus a strict policy of deportation. The states have not challenged DHS’ prosecutorial discretion to not prioritize the removal of certain illegal aliens. Instead, this case is about whether DHS can grant benefits in contravention of the immigration scheme established by Congress. The grant of benefits is an affirmative agency action, and under the law there is a strong presumption that courts can review agency action.

Barring any truly odd circumstances, it is a safe bet, given how late the argument in this case will be heard and the likely contentious opinions among the justices, that this case, along with the abortion reform case Whole Women’s Health v. Cole and the seven consolidated contraception mandate accommodation cases, will be among the last set of opinions issued by the Supreme Court before the term ends in June. Whether the high court intended it or not, that will launch this issue into the spotlight at the height of the election.