The 4th Amendment to the Constitution: A Primer

The 4th Amendment is among the most sacred safeguards of individual liberty embedded in our Constitution.

The amendment reads:

“The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.”

In just 54 words, the 4th Amendment packs a lot of significance, and interpreting their meaning has kept judges and lawyers busy for centuries.

The basic premise of this amendment is to protect Americans from unreasonable searches and seizures of their property by the government. (Keep an eye on the word “unreasonable,” because it’s going to be important.)

It is for this reason that a police officer cannot stop you while you’re walking down the street and arbitrarily search your purse or pockets.

These protections did not just come about spontaneously. Like all amendments included in the Bill of Rights, the Framers learned from their experience as royal subjects and added safeguards against the abuses they routinely endured by British agents.

The 4th Amendment: The basics

To better understand why the ratification of the 4th Amendment was so important to our Framers requires a deep dive into the historical context of 18th-century colonial America.

The colonists, still under the thumb of the British king, were subject to arbitrary and invasive searches under the “Writs of Assistance,” which allowed British troops and government officials to search homes and private property looking for goods that were imported illegally or on which a tax had not been paid. Needless to say, such abuses were a sore point for the aggrieved colonists.

A particularly notable figure of the colonial revolutionary era is James Otis, a Massachusetts lawyer and political activist who has been described as “the Founding Father of the 4th Amendment.”

In a famed 1761 oration against the Writs of Assistance, Otis painted a vivid portrait of how unlimited government search powers were a threat to the liberty and tranquility of the people:

“Now one of the most essential branches of English liberty is the freedom of one’s house. A man’s house is his castle; and while he is quiet, he is as well guarded as a prince in his castle.

 This writ, if it should be declared legal, would totally annihilate this privilege. Custom-house officers may enter our houses when they please; we are commanded to permit their entry. Their menial servants may enter, may break locks, bars, and everything in their way; and whether they break through malice or revenge, no man, no court can inquire. Bare suspicion without oath is sufficient. This wanton exercise of this power is not a chimerical suggestion of a heated brain…”

In making the case against the “wanton exercise of this power” over the American colonists by agents of the British crown, Otis articulated the intellectual and moral principles that would later come to undergird the 4th Amendment in the Bill of Rights. He thus laid the groundwork to ensure that such abuses of power would not be allowed to continue, should America earn its independence.

A young John Adams was in the audience when Otis gave this speech and later wrote “then and there the child independence was born.”

The principles passionately supported by Otis would come to serve as the foundation of individual liberty, private property protection, and privacy law.

So next time you see a television cop taking time to secure a search warrant from a judge to allow him to pursue an investigation against a criminal suspect, you’re watching the 4th Amendment in action—and you can thank James Otis for that.

Key cases in 4th Amendment history

Over the past century, the 4th Amendment has grown in importance, owing to the expansion of government powers and the rapid pace of technological change. During that time, the courts have paid increasing attention to 4th Amendment issues.

A particularly important landmark was the Supreme Court’s decision in Weeks v. United States (1914), which established that evidence obtained through unconstitutional means was inadmissible in court. This is known as the “exclusionary rule,” which is important because it provides an incentive for law enforcement personnel and other government agents to be scrupulous in respecting 4th Amendment protections.

Another seminal case in 20th-century 4th Amendment jurisprudence was Katz v. United States (1967). Charles Katz was a sports gambler known for his skill at handicapping college basketball games. Unfortunately for Katz, his gifts brought him to the attention of federal investigators. Seeking to avoid law enforcement scrutiny, Katz often used a public phone booth near his Los Angeles apartment to conduct his less-than-legal business affairs. To build the case against him, the FBI tapped the phone booth, which resulted in criminal charges and a conviction against Katz.

Katz appealed his case, but the 9th Circuit upheld the search because it did not penetrate the telephone booth’s walls. However, the Supreme Court reversed the lower court’s call, throwing out the FBI’s wiretap evidence and overturning Katz’ conviction based on the new doctrine of a “reasonable expectation of privacy.”

This was a landmark moment for privacy law: by divorcing the 4th Amendment from concepts of property invasion, the Court fundamentally altered the jurisprudential landscape surrounding government searches and seizures.

While in some respects this decision expanded individual protections against government snooping, in other respects it weakened the protection against incursions on private property. Moreover, no one has ever been able to come up with a good explanation of exactly what a “reasonable expectation of privacy” is supposed to mean.

Recent cases

In reaction to the imprecision of the “reasonableness” standard, lawyers and scholars with an interest in property law have sought to rejuvenate 4th Amendment jurisprudence with a renewed focus on incursions on private property rights. Along those lines, key 4th Amendment cases from the past couple of decades include the following:

• Kyllo v. United States (2001), in which the Court held that thermal imaging of a home (to look for heat from grow lights) required a warrant under the 4th Amendment.
• United States v. Jones (2012), in which the Supreme Court determined that installing a GPS tracking device on a suspect’s car was a search under the 4th Amendment and that the police exceeded the scope of their warrant. The Court held this was a trespass against the car owner’s personal property.
• Florida v. Jardines (2013) dealt with the question of whether a drug-sniffing dog on the front porch of a private home required a warrant, distinguishing the case from similar searches in public places like airports. The court decided that yes, a warrant was required.
• Carpenter v. United States (2018) focused on government acquisition of cell-site records. The Court held that the government’s perusal of 127 days of a suspect’s cell-site data required a warrant.
• Lange v. California, now pending before the Supreme Court, in which the police entered a private home without a warrant in order to arrest a person allegedly fleeing arrest.
• Caniglia v. Strom, also currently pending before the Supreme Court, deals with the question of whether the police should have entered a home without a warrant to seize guns owned by a husband who had been sent to a hospital for observation after a marital dispute.
• Cedar Point v. Hassid, slated to be argued before the Supreme Court on March 22, weighs the question of whether California agricultural growers’ property rights are violated by a state regulation allowing union organizers to enter their property unannounced and without the owners’ permission. While the 4th Amendment is not directly at stake, the case deals squarely with what kind of privacy you can expect on your property.

Challenges for the 4th Amendment

As noted above, the growth of government’s enforcement powers and the proliferation of technological changes have opened up new frontiers for potential 4th Amendment violations that challenge traditional understandings of “search and seizure.”

For example, PLF’s has written about the questions surrounding digital privacy with regard to potentially intrusive technologies like surveillance and digital tracking, urging greater protections for individuals against potential violations of privacy.

“Many digital privacy cases working their way through the courts now are incredibly important in defining what types of digital privacy the 4th Amendment protects,” Woislaw notes. “The 4th Amendment is our best line of defense against the pervasive surveillance state—so now is the time for judges to clarify with greater precision how the Constitution protects digital privacy.”

Likewise, there are also issues dealing with “administrative searches” that permit government to search the physical sites of “highly regulated industries” with minimal warrant protections. These include gun shops, liquor stores, bars, industrial facilities, and the like. It’s another area where courts should look to rein in potential government abuses of 4th Amendment rights.

Such challenges only underscore the fact that protection of private property from government search is a key to securing individual liberty for all Americans.

The 4th Amendment is much more than a matter of criminal procedure—by limiting the power of government to target citizens through unreasonable searches and seizures, it’s one of our most important bulwarks in defense of privacy and individual liberty. It is essential, therefore, that the protections to private property granted by the Constitution’s 4th Amendment (and its close neighbor, the Fifth Amendment) be zealously guarded.