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The Search and Seizure Law of State Constitutions

Massachusetts is on the front lines of a movement toward independent state constitutional rights.


When law students learn the substantive criminal law, which typically takes place within the 1L year, they sometimes become distressed at having to learn multiple rules for most everything. But that is simply a blessing of federalism — when you have 52 criminal jurisdictions (50 states, the federal government, and the District of Columbia), variation is only natural, and so we must study at least a small slice of that variation to understand anything meaningful about American criminal law.

Yet when those students reach a criminal procedure course concerning the constitutional regulation of policing, they are delighted to learn a single (albeit complicated) set of rules: those articulated by the U.S. Supreme Court interpreting the federal Constitution’s Fourth, Fifth, and Sixth Amendments. Unfortunately, something critical is missing, as we can see by looking to the structure of our American founding.

As either James Madison or Alexander Hamilton expressed in Federalist 51 (precise authorship is uncertain), “In a single republic, all the power surrendered by the people is submitted to the administration of a single government; and the usurpations are guarded against by a division of the government into distinct and separate departments.” In other words, under Montesquieu’s separation of powers, power is “the rival of power” (Federalist 28), and each government branch (legislative, executive, and judicial) rivals one another. But in America there is more. Returning to Federalist 51, “in the compound republic of America, the power surrendered by the people is first divided between two distinct governments” — federal and state — “and then the portion allotted to each subdivided among distinct and separate departments” — again, separation of powers. “Hence,” the founding essay explains, “a double security arises to the rights of the people.”

A critical aspect of that “double security” is that — at least as to the actions of state (non-federal) officers, and even more generally within the operation of a particular state’s courts — Americans are meant to enjoy two layers of constitutional protection: one enshrined in the federal Bill of Rights and the other in a state constitution. Citizens of the Land of Enchantment (New Mexico) are protected by their constitution, citizens of the Bay State (Massachusetts) by theirs, and so on. And thus we see what is missing from the criminal procedure curriculum in law schools: upper-level criminal procedure students ought to confront alternative rules just like those 1Ls learning the substantive criminal law, since every state constitution has an analogue or cognate to the federal Fourth Amendment. For example, New Mexico’s constitution includes Article II, Section 10, and the Massachusetts Declaration of Rights contains Article XIV.

Admittedly, while there has been longstanding, significant divergence in substantive state criminal law, for much of American history there was very little development of state constitutional rights, including those related to criminal procedure. And the language of state search and seizure provisions is often nearly identical to the federal, encouraging state courts to interpret these provisions in lockstep with federal interpretation of the federal Constitution. And while in 1932 Justice Louis Brandeis famously noted the potential for state “laboratories of democracy,” it was not until the 1970s that a so-called “new federalism” of meaningful independent interpretation of state constitutions really took root. Only within the last two decades has such interpretation begun to mature in the policing context. But that maturation is real, even to the point where it is feeding back into the U.S. Supreme Court’s interpretation of the federal Fourth Amendment, even if only as subconscious — yet critical — backgrounding.

For example, consider Massachusetts. In 2014, its Supreme Judicial Court — as the state’s highest court is known — renewed its declaration of independence from federal interpretation in Commonwealth v. Augustine. There, the court decided that a state resident retains a reasonable expectation of privacy in her location records residing with her cellular telephone company, and therefore that police could obtain extended historic cell site location information only pursuant to a judicial warrant supported by probable cause. The U.S. Supreme Court held much the same in Carpenter v. United States, as a matter of federal Fourth Amendment rights that apply to all of us, whether Bay Stater or Okie. But that’s just it: the Massachusetts high court so held as a matter of its state constitutional law in 2014, and then the U.S. Supreme Court effectively followed as a matter of federal constitutional law in 2018 — a development I often argued for before it came to fruition in Carpenter.

Augustine is thus a benchmark, signaling a new federalism for the Fourth Amendment and its state analogues. Today, a decade post-Augustine, Massachusetts’s interpretation of its state cognate is sufficiently well developed that opinions rely nearly entirely on the state court’s own work, merely weaving in a nod to federal courts’ Fourth Amendment work now and again as persuasive authority. Consider the 2022 case Commonwealth v. Perry, in which the Supreme Judicial Court permitted very-limited-in-time cell tower dumps if supported by probable cause warrants that include protocols for protecting the privacy interests of everyone not found to be a target. For example, imagine that police believe the same perpetrator committed several robberies, as did police in Perry. And imagine further that police believe two persons were involved, and that those two might have been communicating by mobile phone during the crimes. It stands to reason that investigators would like to know whether there was at least one mobile telephone number in use nearby as each crime was committed.

The way to go about that, I’ve argued, is a process of selective revelation: police ought to ask only whether there is one or more phones used at those several locations at the relevant times. Cellular providers ought to respond only “yes” or “no” and, if yes, how many phones satisfy that criteria and at how many of the locations those phones were used. It is that very correlation — or lack thereof — that either establishes or defeats the necessary probable cause. This approach gets both police what they need and citizens the privacy they deserve.

The Perry court didn’t quite get that far. (And since not doing so both makes it harder on police and less secure for citizens, hopefully a future litigant might continue to nudge.) But the court’s holding did reasonably well protect the privacy rights of Massachusettsans by requiring for cell tower dumps, as a matter of its state constitutional authority, a probable cause warrant including a protocol for the ultimate destruction of non-responsive records. And so, when a case concerning cell tower dumps ultimately reaches the U.S. Supreme Court under the Fourth Amendment — and one will — Massachusetts courts will again have led the way, or at least presented a way the federal high court could choose to follow.

Such leadership would have made the Commonwealth’s first residents, including the fiery James Otis and the proud John Adams, very happy. Those Bay Staters of course led at our revolution — albeit for (as my research has developed) extremely personal reasons, including a family feud and a desire to highlight Massachusetts over Virginia. Today, Massachusetts is again on the front lines, this time in a movement toward meaningfully independent state constitutional rights against unreasonable search and seizure.

Stephen Henderson is the Judge Haskell A. Holloman Professor of Law at the University of Oklahoma.

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