Final Version, "Cross-Enforcement of the Fourth Amendment"

Fresh off the law review presses.


I'm pleased to say that my latest article has just been published: Cross-Enforcement of the Fourth Amendment, 132 Harv. L. Rev. 471 (2018). Here's the abstract:

This Article considers whether government agents can conduct searches or seizures to enforce a different government's law. For example, can federal officers make stops based on state traffic violations? Can state police search for evidence of federal immigration crimes? Lower courts are deeply divided on the answers. The Supreme Court's decisions offer little useful guidance because they rest on doctrinal assumptions that the Court has since squarely rejected. The answer to a fundamental question of Fourth Amendment law — who can enforce what law — is remarkably unclear.

After surveying current law and constitutional history, the Article offers a normative proposal to answer this question. Each government should have the power to control who can enforce its criminal laws. Only searches and seizures by those authorized to act as agents of a sovereign trigger the government interests that justify reasonableness balancing based on those interests. The difficult question is identifying authorization: questions of constitutional structure suggest different defaults for enforcement of federal and state law. Outside the Fourth Amendment, governments can enact statutes that limit how their own officers enforce other laws. The scope of federal power to limit federal enforcement of state law by statute should be broader, however, than the scope of state power to limit state enforcement of federal law.

There's a Volokh-Conspiracy-related angle to this article, although it's pretty obscure. Long-time dedicated readers may remember that back in 2008, before the oral argument in Virginia v. Moore, I became super-interested in the constitutional status of United States v. Di Re. Was that case applying the Fourth Amendment, or was it based in the supervisory power? I was pretty sure it was the former, although others disagreed. Almost a decade later, when I started researching this article, I was amazed to see that the Supreme Court's answer to the questions I was studying seemed to hinge on determining the constitutional status of United States v. Di Re. Years later, I think I finally answered the riddle, see pages 508-514. I guess everything ends up being relevant somehow.

NEXT: The Amy, Vicky, and Andy Act Is Signed Into Law

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  1. “The scope of federal power to limit federal enforcement of state law by statute should be broader, however, than the scope of state power to limit state enforcement of federal law.”

    I’ll have to read the article, but aren’t there 10th Amendment concerns here? The federal government, famously, cannot commandeer state law enforcement resources to enforce federal law.

    1. There’s no commandeering issue here, I think, as the federal government is not forcing or even encouraging states to enforce federal law. Instead, the issue is how the Fourth Amendment applies when a state officer, acting on his own or at the state’s direction, searches or seizes in a way that enforces federal law.

      1. Professor Kerr,

        I don’t understand your answer.

        Wouldn’t the breadth of state power “to limit enforcement of federal law by statute” only come into play when a state statue prohibits a state officer from conducting a search or seizure for purposes of enforcing a federal law? Why wouldn’t searches and seizures be analyzed under the same 10th Amendment analysis as any other state statute prohibiting state officers from taking actions to assist the enforcement of federal laws?

        Perhaps the issue here is that in this case, if a state officer conducted the search/seizure in defiance of a state-law ban, the person attempting to suppress the search/seizure would challenge it on 10th Amendment grounds, not 4th Amendment grounds, so it wouldn’t be considered a 4th amendment issue? Is this the distinction?

        If so, why wouldn’t the admissibility rules for a search/seizure that’s unauthorized (albeit for 10th Amendment reasons) not be evaluated under 4th amendment principles?

  2. Both federal and state, as well as local, law enforcement share commonalities of concern. To divide (and conquer) is to permit inconsistency in the laws application. Much like a criminal who commits crime in city A should not evade enforcement by traveling into city B, so state and federal laws share a common purpose. Should federal law enforcement turn a blind eye if domestic violence occurs in their presence? Should city law enforcement not respond to bank robberies? This parsing and limiting of who can enforce makes the public less safe.

    1. Well, that’s a different question. If a crime occurs in front of you, even a citizen can make an arrest. So surely the “wrong” law enforcement agency can too.

      That’s different from whether they should be obtaining search warrants and making searches, though.

      1. Not if you work at CVS.

  3. This is a good question…and I’m leaning towards no, there should not be cross-enforcement of the Fourth Amendment with the key word being ‘enforcement.’

    Feds don’t know all the different state laws (e.g. motorcycle helmut law, so they shouldn’t stop someone in New Hampshire for riding a motorcycle without a helmut), and vice versa for state LE.

    If they suspect a crime/violation, then they should notify the appropriate authorities.

    Of course, anything violent and in-progress (e.g. bank robbery, shootout), should be immediately addressed from a self-defense/defense of life point of view.

    1. To add to this, the law doesn’t even concern itself with whether the officer knew of the law he was enforcing. It allows ex post justifications. A ruling on this issue would mean that an officer with no known justification for stopping somebody could later justify the stop if he possessed Probable Cause to believe a state or federal offense had been committed. And then you could go further – what about extraterritorial application of state laws (a Credit Card Fraud case where the State claims jurisdiction for use outside of the state if the harm was in the state)?

  4. The federal GFSZA is, in my opinion, one of the worst federal laws on the books. It turns hundreds of thousands of law-abiding gun owners into law-breakers. It nullifies all currently existing reciprocity agreements. It is virtually impossible for anyone living in all but the most remote locations to not pass within 1,000 feet of any school property boundary in their day-to-day activities.

    If there is any potential for abuse of this scenario (state authorities conducting searches based on violation of federal law), the GFSZA provides the way. The majority of states now allow permitless open carry, and nearly 25% of the states allow permitless concealed carry. Each and every one of those law-abiding citizens could fall into such a trap. The BATFE has stated that reciprocity agreements do not satisfy the GFSZA exemption, making every person carrying outside their home state based on a reciprocity agreement also subject to this trap.

    If this practice ever becomes sanctioned by a Supreme Court decision, there could be no end of abuse by local law enforcement agents and even entire agencies who just hate guns in the hands of the citizens.

    1. I bet when the Republicans have control of both Congress and the presidency, then this’ll be rescinded.

      Oh wait. . . .

      1. Remind me, when did Republicans have the 60 votes required to stop a filibuster in the Senate?

        1. Technically, the republicans don’t need 60 votes to stop a filibuster in the Senate.

          The 60 vote requirement is merely internal Senate rules.

          However, despite the Senate having a very old rule that purports to require 60 votes for rule changes, there is SCOTUS precedent that predates the Civil War that as parliamentary bodies, both the Senate and the House have the right to change their own rules at any time by simple majority vote. This is based in part on the principle that past Congresses can’t bind future congresses.

          This is the “nuclear option” that effectively* eliminated the filibuster for judicial nominees.

          If the Senate majority wants to do something badly enough, they can put an end to any filibuster without needing 60 votes to do so.

          *Technically, they didn’t actually prohibit filibusters for judicial nominees, what they did was lower the threshold for a cloture vote to force an end to a filibuster of a judicial nominee from 60 votes to simple majority, rendering attempts to filibuster judicial nominees pointless.

          1. And, also technically, the “nuclear option” isn’t a procedure to change the rules, it is a procedure to appeal an interpretation of the rules. Senate rules require 60 votes to change the rules, but overruling the president only requires a majority.

            1. “Senate rules require 60 votes to change the rules, but overruling the president only requires a majority.”

              You apparently didn’t bother to fully read my comment. That Senate rule requiring 60 votes to change the rules was declared invalid by SCOTUS a long time ago (before the Civil War).

              1. Matthew, I apologize. I posted a “technically” comment and didn’t bother to get the technicalities right. I even got the number of votes wrong.

                Changes to the standing rules do only require a majority, but they involve a motion that is debatable and, therefore, filibuster-able. Cloture on a motion to amend the rules requires two thirds of the members present in favor, as opposed to other cloture votes that require three fifths of the members duly chosen and sworn.

                1. “Cloture on a motion to amend the rules requires two thirds of the members present in favor,”

                  Any such rule is void unless it’s in the constitution itself, which this isn’t. There is standing Supreme Court precedent that the Senate has an absolute right to change it’s rules by simple majority vote.

                  1. I’m aware of attempts to challenge the rule, e.g. Judicial Watch v. US Senate, but as far as I know they have all foundered for lack of standing (any cite to the contrary is welcome). Maybe you’ll be right if one ever gets to the merits.

                    Interestingly, some dismissals question not only the injury-in-fact leg of standing but also redressibility. The court can’t write new rules for the Senate, so goes the reasoning, the most it could do would be to declare void Rule XII that provides for cloture. But that would leave the Senate in the condition that obtained before 1917, with no means to limit debate, and that would not provide relief for whatever injury was claimed.

                    1. The SCOTUS decision I am referring is from before the US Civil War (the 1830s IIRC).

          2. Yup. If they chose, the Republicans could end the filibuster only for repealing gun laws.

  5. Haven’t read your article in its entirety, but how would your proposed rule apply to enforcement of the law of another country?
    Does a Federal law enforcement officer have any greater interest in enforcing a state’s law than in enforcing the law of another country? The test you propose on p.522, whether, for example, the state’s interest in having its traffic laws enforced is vindicated by a stop by a Federal officer, would seem to apply equally to a Federal officer’s enforcement of foreign law. What’s the limiting principle here? Doesn’t the Lacey Act, which in effect Federalizes enforcement of certain laws of other countries, suggest that cross-enforcement of foreign law has to be considered in this analysis?

  6. State and federal territorial jurisdictions overlap, a rare occasion with respect to foreign law.

    The Lacey Act defines a civil offense one element of which can involve the violation of a foreign law, that is not the same thing as enforcing the foreign law. Kenya’s Wildlife Conservation and Management Act (2012) makes unlawful killing of a lion, elephant, leopard, or rhino punishable by up to 10 years imprisonment, but the Lacey Act violation on importing the trophy into the US gets only an (additional) fine.

    1. Re Lacey Act, there’s not much difference between directly enforcing a foreign law according to its terms or importing some or all of that law into a Federal statute which may have a different sanction. The fact remains that an essential element of the Federal law involves violation of a foreign law even where no violation of a domestic law (other than Lacey itself) has occurred. And without benefit of research I’m not sure that concurrent territorial jurisdiction is required for cross-enforcement. Are you saying that a Federal agent can’t enforce violation of a Texas statute (which authorizes cross-enforcement for felonies) if the accused happens to be found in Arkansas? I didn’t think that current cross-enforcement doctrine required that the accused be apprehended in Texas.

  7. I wish judges were more cross (at cops) when enforcing the Fourth Amendment.

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