Are federal law enforcement officers under the command and control of elected officials, or are they free to enforce the law as they choose, targeting the people they want to target, without guidance from an elected leader?

That’s the fundamental question in United States v. Texas, a case that just arrived at the Supreme Court on its “shadow docket.” It asks whether the Biden administration can instruct federal Immigration and Customs Enforcement (ICE) agents to follow certain enforcement priorities when deciding which undocumented immigrants to apprehend and remove from the country.

Anyone with even a passing familiarity with federal immigration law will be baffled that this issue required litigation, much less that it needs to be resolved by the Supreme Court. Federal law provides that the secretary of Homeland Security “shall be responsible” for “establishing national immigration enforcement policies and priorities.” Thus, immigration enforcement agencies such as ICE are under the control of a senior political official who is responsible to an elected president.

Pursuant to this authority, Secretary Alejandro Mayorkas issued a memo to ICE’s acting director last September, informing him that the agency should prioritize its enforcement efforts against undocumented or otherwise removable immigrants who “pose a threat to national security, public safety, and border security and thus threaten America’s well-being.”

Not long after Mayorkas issued this memo, however, the Republican attorneys general of Texas and Louisiana went to Drew Tipton, a Trump judge known for handing down legally dubious decisions blocking the Biden administration’s immigration policies, asking Tipton to declare Mayorkas’s memo unlawful. Tipton obliged, and his decision was embraced by an especially right-wing panel of the United States Court of Appeals for the Fifth Circuit.

Now, the Biden administration is asking the Supreme Court to stay Tipton’s decision, temporarily restoring an elected administration’s control over federal law enforcement while this case proceeds.

Though the Supreme Court is dominated by Republican appointees who are often no less ideological than Tipton, it’s possible that as many as six justices will reject Tipton’s unusually weak legal arguments. Last month, a majority of the Court took that approach in another immigration-related case featuring similarly weak legal arguments by a different Trump judge in Texas (although they also left open a few legal questions that judge could exploit to usurp the Biden administration’s immigration powers temporarily).

Still, the stakes in the Texas case are high. ICE employs nearly 8,000 individuals in enforcement and removal operations, many of whom are sworn law enforcement officers who carry a badge and a gun. Either these individuals are under the command and control of political officials — as federal law says that they are — or they are free to set their own priorities without oversight from anyone responsible to the American people.

What federal law actually says about immigration enforcement

There’s no reasonable argument that Mayorkas does not have the authority to set enforcement priorities for ICE, and for other immigration law enforcement agencies. As noted above, a federal statute explicitly empowers him to do so, and the then-secretaries of Homeland Security issued similar memos setting enforcement priorities in 2000, 2005, 2010, 2011, 2014, and 2017.

One reason why Mayorkas must set these priorities is that Congress has not provided the Department of Homeland Security with enough resources to apprehend and deport every undocumented immigrant in the United States even if it wanted to. As the Justice Department noted in a 2014 memo, “there are approximately 11.3 million undocumented aliens in the country,” but Congress has only appropriated enough resources to “remove fewer than 400,000 such aliens each year.”

Moreover, even if a federal statute didn’t explicitly give Mayorkas the power to establish “national immigration enforcement policies and priorities,” he would still be allowed to order ICE to focus its resources on certain immigrants, and to deemphasize enforcement against others, under a doctrine known as prosecutorial discretion.

Prosecutorial discretion refers to the power of law enforcement officers and their supervisors to decide when to enforce the law and when to decline to do so. If you’ve ever been pulled over by a police officer and then let off with a warning, then you can thank prosecutorial discretion for saving you from a ticket.

The Supreme Court has warned federal judges like Tipton to be very reluctant to second-guess these kinds of discretionary judgments by law enforcement agencies. As the Court held in Heckler v. Chaney (1985), “an agency’s decision not to take enforcement action should be presumed immune from judicial review.”

This presumption, moreover, is especially strong in the immigration context. The Supreme Court has said that “a principal feature of the removal system is the broad discretion exercised by immigration officials.” Even after an enforcement agency decides to bring a removal proceeding against a particular immigrant, the Court explained in Reno v. American-Arab Anti-Discrimination Committee (1999), it “has discretion to abandon the endeavor.” And it may do so for any number of reasons, including “humanitarian reasons or simply for its own convenience.”

So Tipton had no business second-guessing Mayorkas’s judgment. The secretary of Homeland Security doesn’t simply have explicit statutory authority permitting him to set immigration enforcement priorities, he also can rely on a body of Supreme Court decisions holding that the executive branch — and not the judiciary — gets to decide enforcement priorities generally.

Tipton’s opinion is embarrassing

In blocking Mayorkas’s memorandum, Tipton also made a number of errors that are so basic they can be refuted in a few sentences.

Tipton, for example, claims that Mayorkas was required to complete a process known as “notice and comment,” which can take months or even years, before he can set enforcement priorities for ICE. But federal law exempts “general statements of policy” from notice and comment, and the Supreme Court defines the term “general statement of policy” to include “statements issued by an agency to advise the public prospectively of the manner in which the agency proposes to exercise a discretionary power.”

Again, Mayorkas has the discretionary power to set enforcement priorities for ICE.

Similarly, Tipton faulted Mayorkas’s memo because it supposedly failed to consider “the costs its decision imposes on the States.” But a 21-page document accompanying Mayorkas’s memo includes an entire subsection titled “Impact on States.” That subsection concludes that “none of the asserted negative effects on States — either in the form of costs or the form of undermining reliance interests” — undercut the benefits of Mayorkas’s preferred policy.

Tipton’s opinion, in other words, takes such extraordinary liberties with the law and with the facts of this case that there is a very real possibility that even this Supreme Court, with its 6-3 conservative supermajority, will determine that he went too far. It is notable that, shortly after Tipton handed down his decision, a federal appeals court in Ohio rejected Tipton’s arguments and sided with Mayorkas’s power to set enforcement priorities.

That decision was written by Chief Judge Jeffrey Sutton of the Sixth Circuit, a conservative Bush appointee who the late Justice Antonin Scalia described as “one of the very best law clerks I ever had.”