This commentary was originally featured in The Hill on March 1, 2018. 

May the government monitor your internet habits or the location of your cell phone without a warrant? The United States Supreme Court will soon decide.

This year, the court could decide as many as three cases involving the scope of the Fourth Amendment in the digital age. If the oral arguments in these cases are any indication, the advancement of digital forms of communication, like the internet, has stretched the court’s 20th-century framework for Fourth Amendment cases to its breaking point. Justice Gorsuch, however, hinted at a counterintuitive solution — return to the original property rights-based approach to the Fourth Amendment developed at our nation’s founding.

As understood in the 1790s, anything considered a trespass to person or property would be a search under the Fourth Amendment. That remained the standard until the 20th century, when the court adopted the current “reasonable expectation of privacy” test in Katz v. United States. Ironically this modern standard, not the one from the 18th century, is ill-suited for the digital age.

In Katz, the court was asked if planting a listening device on a phone-booth was a search under the Fourth Amendment. The problem, as the court saw it, was that the device could be utilized without invading an individual’s person or property — hence, no trespass and no search. The justices, however, intuitively understood that secretly listening in on a private phone call is the type of activity the Fourth Amendment was designed to protect against. So the court created a new constitutional test out of whole cloth: If the government surveillance invades an area where a person has a “reasonable expectation of privacy,” then it is a search.

While the Katz court came to the right conclusion, the problems with the artificial standard it created to reach that conclusion are becoming increasingly obvious. As technology changes, so does the government’s ability to surveil previously private activities. As that surveillance becomes more well known, people cease to have an expectation that their activities are private. Under Katz, as that expectation decreases, so do Fourth Amendment protections. So, ironically, the test designed to protect Fourth Amendment rights as technology advanced has the opposite effect — as technology advances, Fourth Amendment protections decrease.

We see this failing on full display in cases currently before the court involving government surveillance of cell phone GPS data and internet browsing history. In both cases, the government claims data are not protected, because most individuals know that their cell phone or internet service provider has the capability to track their phone or browsing history. Hence, there is no reasonable expectation of privacy. The court now appears to be struggling with the difficult task, under Katz, of determining what the public reasonably understands about cell phone and internet service.

The irony is that such cases are far simpler and more protective under the 1790’s framework, if rightly applied. If we treat the Fourth Amendment like every other right, the question is whether, but for this advanced technology, the government action would require a trespass to person, or property? In other words, could the government have collected this information in 1790 without invading your space?

The court dabbled with this approach several years ago, in Kyllo v. United States, which found the use of thermal imaging devices by police to look inside homes without a warrant was an unconstitutional search. Writing for the court, Justice Scalia noted that, “obtaining by sense-enhancing technology any information regarding the interior of the home that could not otherwise have been obtained without physical intrusion into a constitutionally protected area, constitutes a search.” But the court expressly limited its opinion to the home and refused to overturn Katz. It shouldn’t have.

Applied to modern cases involving the internet, as well as the situation in the Katz case itself, this original property rights-based approach is both simpler and more protective than the test created in Katz. In 1790, the government couldn’t track something in your pocket without searching you, it couldn’t tell what you were reading at night without invading your home, and it couldn’t listen to your conversations in a booth without hopping in there with you. It should not be able to do those things today, simply because technology has advanced.

We didn’t apply a new First Amendment standard when newspapers switched to digital formats. We don’t need a new Fourth Amendment standard for the internet.We just need to enforce the amendment’s original meaning.