Last week, the Supreme Court granted cert in a Fourth Amendment case, Lange v. California, that asks whether a police officer in “hot pursuit” of a suspected misdemeanant must get a warrant before entering the suspect’s home. That question turns out to be momentous for several reasons, two of which are obvious and one of which is less so but may be even more profound.

First, the vast majority of arrests in this country are for misdemeanors. Citing our friend Alexandra Natapoff, Lange’s cert petition notes that “[r]oughly thirteen million misdemeanor cases are filed each year, outnumbering felonies by four to one.” Indeed, as Prof. Natapoff documents in her wonderful book, Punishment Without Crime: How Our Massive Misdemeanor System Traps the Innocent and Makes America More Unequal and in this interview, “[t]he misdemeanor system represents 80 percent of the state criminal dockets in this country.” Thus, contrary to Justice Souter’s misperception in one of the Supeme Court’s most important misdemeanor cases, Atwater v. City of Lago, we certainly are “confronting … an epidemic of unnecessary minor-offense arrests.” Moreover, as Prof. Natapoff and others have documented, arrests for even minor offenses can have devestating effects on people’s lives. Among other things, misdemeanors “are moneymakers for local jurisdictions,” and the fines, court fees, and other monetary penalties they impose can result in crushing debt and a cascading financial crisis from which it becomes impossible for many people to escape. Besides the direct financial implications, a misdemeanor conviction can have serious collateral consequences, including loss of employement, housing, and eligibility for various government benefits. In short, contrary to what you—or, perhaps more to the point, many judges—might think, a misdemeanor arrest is a really big deal.

Second, allowing police officers to storm into people’s houses unexpectedly is a terrible idea, as at least some judges have understood for several hundred years. As recounted in an amicus brief filed by the National Assocation of Criminal Defense Lawyers (NACDL), a 1757 case from England involved “a murder conviction of a man who reacted to a peace officer’s entry into his friend’s workshop by striking the officer dead with an ax.” As the judge in that case recognized, occupants must be told whether an officer barging into a home or office “cometh as not as a mere trespasser, but claiming to act under proper authority.” Fast forward two centuries to a case where an American plainclothes detective pried open the window of a rooming house to investigate a suspicious noise, startling the landlady, and we see Justice Robert Jackson presciently warning that “[m]any home-owners in this crime-beset city doubtless are armed. When a woman sees a strange man, in plain clothes, prying up her bedroom window and climbing in, her natural impulse would be to shoot [him].” If anything, this concern has only grown more acute as police have become more militarized and more people have chosen to exercise their constitutional right to own a gun at home for self defense. Underscoring that point, the NACDL’s amicus brief describes a number of hairraising incidents where police barged into a home without a warrant in “hot pursuit” of supsected misdemeanants—including a young man who relieved himself on a corner of his girlfriend’s outdoor patio—with sometimes tragic results. In short, there have always been compelling reasons to be extraordinarily careful about allowing armed agents of the state to come storming into people’s homes unannounced, even if they conflict with the government’s strong preference for volume and efficiency in the administration of criminal justice.

And that takes us to the third reason why Lange is such a compelling case and why it’s vital that the Supreme Court get it right. As I have argued elsewhere, one of the most important things to understand about our criminal justice system is the way it has moved from the essentially individualizaed, retail operation that the Founders envisioned to the industrial-scale, assembly-line operation it has become today. As Professors Chris Surprenant and Jason Brennan document in their new book, Injustice for All: How Financial Incentives Corrupted and Can Fix the US Criminal Justice System, “policing and punishment is big business in the United States.… All included, it is at least a $300-billion-a-year industry” employing some three million people whose jobs depend on keeping the entire pipeline—from arrest to incarceration—chock full at all times. And while felonies get the most attention, recall that there are four times as many arrests for misdemeanors. So is it reasonable to suppose that police officers, whose professional bread-and-butter is making misdemeanor arrests, would prefer a system that makes them as easy and hassle-free as possible? Of course it is.

Just consider the facts of the Lange case itself. The arrest arose out of Officer Aaron Weikert’s decision to pull Mr. Lange over for playing loud music and honking his horn. But instead of pulling over when Weikert activated his lights, Lange—who was nearing his home and says he did not see Weikert behind him—continued driving a few seconds, then turned into his driveway and parked in his detached garage. Weikert parked and walked up the driveway in time to stop the garage door from closing with his foot. He then entered the garage—without a warrant and without seeking consent—and began questioning Lange. Claiming he could smell alcohol on Lange’s breath, Weikert ordered Lange outside for a DUI investigaiton and ultimately charged him with driving under the influence.

Now ask yourself what would have happened if, as Lange urges in his cert petition, Officer Weikert had been required to obtain a search warrant before entering Lange’s garage in order to question him about his loud music and horn-honking. Most likely, Weikert would have considered it a waste of time—not just his own but particularly the judge’s—to apply for a warrant under the circumstances and would never have ended up questioning Lange in his garage that day.

This is key because so many encounters between police and citizens amount to fishing trips where police use a traffic infraction or other minor offense to ask incriminating questions, check for outstanding arrest warrants, or simply get a whiff of somebody’s car, backpack, or breath. And the longer police can prolong the encounter—long enough, say to get a probable-cause-creating (aka “drug-sniffing”) dog to the scene—the better their chances of making an arrest.

Indeed, much of modern criminal justice involves actors within the system simply following the path of least resistance, regardless of whether it makes society any better off. For example, marijuana arrests continue to outnumer arrests for violent crimes, even as clearance rates for homicides and other violent crimes plummet. Can there be any doubt that every single dollar spent arresting and processing people for simple marijuana possession would have been far better spent catching murderers, rapists, and armed robbers?

The truth is, we criminalize far too much conduct, with the result that police and other actors in the criminal justice system are asked to do too much have far too much opportunity to devote their efforts to activities that provide little social benefit but impose terrible costs on individuals—including humiliation, incaceration, and permanent financial ruin, to name but a few.

The constitutionally prescribed process of arresting, prosecuting, and convicting someone was deliberately designed to be cumbersome and expensive, and therefore not something to be undertaken lightly. But the government has been extraordinarily successful in hacking that process, in effect turning what was meant to be a social-utility-maximizing criminal justice system into an implacable conviction machine that gobbles up vast quantities of citizens and spits out convicts.

What are some of the ways the government has hacked the protections we were meant to enjoy?

One is by designing various legal frameworks—the traffic code at issue in the Lange case is a prime example—that make it practically impossible for ordinary citizens to go about their business without giving police some legal basis (even a purely pretextual one) to detain them and see if they can turn up evidence of any other infractions.

Another is by criminalizing vast amounts of non-morally-wrongful behavior that perfectly decent, otherwise law-abiding people wish to engage in, believe they have a right to engage in, and will continue to engage in despite the fact that it is illegal to do so. Examples include everything from wearing saggy pants, to growing the wrong not-particularly-harmful plant in your back yard, to owning the wrong kind of hunting rifle.

But the most significant hack—the one that represents the true sine qua non of mass incarceration—was when the government discovered how to streamline the cumbersome adjudicative process prescribed by the Constitution and drive the cost-per-criminal-conviction down from tens or hundreds of thousands of dollars per unit to almost nothing. We refer to that hack as “plea bargaining,” but that’s an ignoble lie we tell ourselves in order to avoid confronting the fact that American-style plea bargaining has become pervasively coercive and is increasingly difficult to distinguish from the use of judicially sanctioned torture in pre-Enlightenment Europe to extract confessions from the guilty and innocent alike.

The bottom line is this: No one knows exactly how many people should be locked up at any given time. Given our penchant for overcriminalization, we can be confident that the correct number is fewer than the total number of “offenders”; but without some rational system for ensuring that the government only decides to go after people—and potentially ruin or even end their lives—when their conduct truly merits that response, our criminal-justice system will be driven more by the insatiable appetite of the conviction machine than by the best interests of society.

Our criminal justice system was designed to be relatively inefficent and to ensure the government would not bring that sanction to bear willy-nilly. Those are features, not bugs. Simply put, if the conduct at issue isn’t worth the time and effort of getting a warrant—or the expense and inconvenience of a jury trial—then maybe it’s not worth ruining somebody’s life over either. Let’s hope the Supreme Court sees it that way in Lange anyway.