At the end of a recent talk on the Supreme Court’s latest term I was asked what surprised me most about the term. I was not surprised by the results in the most high-profile cases of the term, such as tariffs, presidential removal power, birthright citizenship, and restrictions on transgender athletes. From the oral arguments and from my sense of the justices’ views, I would have predicted these results.
I don’t want to overstate my predictive powers. I was surprised that the birthright citizenship case, Trump v. Barbara, was 5-4 on whether President Donald Trump’s Executive Order violated the 14th Amendment. In light of the history, the text of the 14th Amendment and its background, precedent, and tradition, I thought it would not be a close case. Similarly, I was surprised that it was 9-0 that the West Virginia law barring transgender girls and women from participating in sports corresponding to their identity did not violate Title IX of the Civil Rights Act, though it was 6-3 that it did not infringe the equal protection clause.
But the question I was asked made me think about what I found most surprising. Here’s my top three choices, one a concurring opinion, one a ruling on the emergency docket, and one a merits decision.
Justice Thomas arguing that the requirement for equal protection does not apply to the federal government
My biggest surprise in reading the decisions was a concurring opinion by Justice Clarence Thomas in Mullin v. Doe arguing that equal protection does not apply to the federal government. The case involved Trump suspending Temporary Protected Status for individuals from Haiti and Syria. One of the issues in the case was whether this was based on race as to Haitians, with Justice Elena Kagan in dissent quoting statements from Trump that seemed to clearly express racial animus. Justice Samuel Alito wrote the majority opinion and said that there was not overt racism and there was an adequate alternative explanation for the president’s actions.
But Thomas, in his concurring opinion, said that equal protection does not apply to the federal government at all. He wrote: “Respondents’ equal protection claim also has no basis in the Constitution. The Constitution has only one Equal Protection Clause, and it applies only to the ‘State[s],’ not the Federal Government.” He said: “Because the Fifth Amendment has no Equal Protection Clause, this Court was wrong to read equal protection into it in Bolling v. Sharpe (1954).”
It is stunning to imagine that the court would say that there is no equal protection limit on the federal government’s ability to discriminate. The court has long assumed that equal protection applied to the federal government. Korematsu v. United States, decided in 1944, was tragically wrong in upholding the evacuation of Japanese Americans from the west coast during World War II, but Justice Hugo Black’s majority opinion left no doubt that it was applying equal protection to the federal government.
In Bolling v. Sharpe, a companion case to Brown v. Board of Education, the court declared unconstitutional the segregation of the District of Columbia public schools. Chief Justice Earl Warren’s opinion for a unanimous court held that equal protection applies to the federal government through the due process clause of the Fifth Amendment. Had the court followed Thomas’ reasoning, it would have ruled that segregated schools are unconstitutional when mandated by state governments, but not a violation of equal protection when imposed by Congress.
Amidst the attention to end-of-term decisions, I think one of the most important rulings, and one that I did not predict, was on Dec. 23, 2025, when the Supreme Court ruled that Trump was extremely limited in his ability to federalize a state’s National Guard. It was a 6-3 ruling and greatly limits the ability of the president to use troops for domestic law enforcement.
The Supreme Court interpreted two federal statutes in coming to this conclusion. One law, 10 U.S.C. § 12406(3), empowers the president to federalize members of a state’s National Guard if he is “unable with the regular forces to execute the laws of the United States.” The Trump administration claimed that it needed to federalize the Illinois National Guard, and similarly those in California and Oregon, because local police were unable to adequately protect ICE agents.
But the Supreme Court said that the statutory provision means that a president can federalize a state’s Guard only if it can be shown that the armed forces of the United States cannot provide adequate protection. In a 6-3 ruling, the court stated: “We conclude that the term ‘regular forces’ in §12406(3) likely refers to the regular forces of the United States military. This interpretation means that to call the Guard into active federal service under §12406(3), the President must be ‘unable’ with the regular military ‘to execute the laws of the United States.’”
This, in itself, is obviously a major limit on the ability of the president to federalize a state’s National Guard. It is hard to imagine situations where the United States military would not be sufficient and would need the assistance of a state’s Guard.
But the Supreme Court went even further. It said that to federalize a state’s Guard, it would need to be a situation where the United States military legally could be used but would be insufficient. Here, a second federal statute is critical. The Posse Comitatus Act, 18 U.S.C. § 1385, adopted in 1878, prohibits the United States military from being used for domestic law enforcement except in very limited circumstances, such as when there is an insurrection in a state. Adopted soon after the end of Reconstruction, the act makes it a federal crime to use the military within the United States except as expressly authorized by the Constitution or a federal statute.
In other words, the Supreme Court said that a president can federalize a state’s National Guard only in the rare circumstances where the Posse Comitatus Act allows the military to be used for domestic law enforcement and only then if the United States military would be inadequate. Specifically, the court declared: “[B]efore the President can federalize the Guard under §12406(3), he likely must have statutory or constitutional authority to execute the laws with the regular military and must be ‘unable’ with those forces to perform that function.”
It is hard to imagine, except in the most dire of circumstances, how these requirements could be met unless the president chooses to invoke the Insurrection Act. The bottom line is that this is a crucial ruling against Trump and a reaffirmation that the military should not be used for policing in the United States.
Although I think I would have done well in predicting the results in major cases this term, I would have gotten it wrong in forecasting Chatrie. It is an enormously important Fourth Amendment case concerning what is a search.
After a bank robbery in Virginia, the police obtained and served on Google a geofence warrant seeking a list of every device within 150 meters of the location of the robbery within one hour of it. After Google complied with this, the police asked for information about the location of some specific devices over a two-hour period. Google provided this information and subsequently identified the subscriber information for three of the devices. One of these devices belonged to Okello Chatrie. The district court denied Chatrie’s subsequent suppression motion and he was convicted.
The issue before the court was whether the police obtaining this information was a search within the meaning of the Fourth Amendment. Justice Elena Kagan wrote the opinion for the court in a 6-3 decision and concluded: “[W]e hold that police officers invade a cell-phone user's reasonable expectation of privacy when they access his Location History. It does not matter if the time period scrutinized was only two hours. Nor does it matter that the materials obtained were handed over by a third-party tech company. When the government ‘accesses historical cell phone location information’—Location History as much as CSLI [cell-site location information]—it ‘conducts a search under the Fourth Amendment.’” The court did not address whether the warrant was sufficient or whether the exclusionary rule (explained below) should apply. The court remanded the case for the resolution of those issues.
Why was this a surprise? First, it is significant that the court reaffirmed and indeed extended its decision from the 2018 case of Carpenter v. United States, where it held that it was a search requiring a warrant based on probable cause when the police obtained 127 days of stored cellular location information about a person. The court’s decision in Carpenter was 5-4, with Chief Justice Roberts’ majority opinion being joined by Justices Ruth Bader Ginsburg, Stephen Breyer, Sonia Sotomayor, and Elena Kagan. Each of the four dissenters – Justices Anthony Kennedy, Thomas, Alito, and Neil Gorsuch – wrote separately to strongly disagree with the majority. With the subsequent change in the composition of the court, and especially Justice Amy Coney Barrett replacing Ginsburg, there was a real question of whether the court might reconsider and even overrule Carpenter. Instead, five justices joined an opinion emphatically reaffirming it and even Barrett in dissent declared that she has “no quarrel with Carpenter.”
In fact, as noted above, Chatrie significantly extends Carpenter. That case was about the police obtaining a large amount of stored cellular location information. In Chatrie, the court made clear that obtaining even a small amount of someone’s location information is a search. This will have important implications for other police investigative techniques such as cell tower dumps (where police obtain a list of all the cellular devices connected to a cell tower at a particular time) or obtaining real-time cellular information (a list of devices connected at the time of the police investigation).
Second, I was surprised that the court addressed the question of whether it is a search even though the law seems clear that in the end the evidence will not be excluded from being used against Chatrie. In 1984’s United States v. Leon, the court ruled that the exclusionary rule does not apply if police rely in good faith on a warrant issued by a judge. That occurred here.
Based on all of this, Alito argued in dissent that Chatrie was an inappropriate advisory opinion, yet one which “will send seismic waves through our Fourth Amendment doctrine.”
Simply put, Chatrie is an important limit on the police, and portends other important limits, from this court.