Does Plea Bargaining Add to Criminal Court Caseloads?

If there is one thing about criminal courts that everyone agrees on, it is—as the Supreme Court has said many times—“plea bargaining is an essential component of the administration of justice” without which our courts “would grind to a halt.” As a result, “‘plea bargaining is . . . not some adjunct to the criminal justice system; it is the criminal justice system’” At first blush, reasons for this seem obvious. More crimes (and more success at catching offenders and gathering evidence) lead to more prosecutions. Because funding for courts and prosecutors hasn’t kept pace with the demands placed on them, officials are forced to find new ways to do more with less—to process criminal cases faster. In some particularly overburdened jurisdictions, such as in southwestern states where immigration cases skyrocketed and greatly overburdened some federal courts, judges have devised even-quicker means of processing cases than ordinary plea bargains. They process large numbers of defendants charged with the same offenses at all once in group hearings. Judges speak to perhaps a dozen defendants at once, collectively informing them of their rights they are about to waive and the consequences of conviction, asking whether anyone has questions, then accepting their guilty pleas. The alternative would seem to be more delays and longer backlogs.

Look at little deeper, though, and the picture is more complicated. Crime rates have been declining for twenty years, and more recently the caseloads in many state and federal courts have been declining as well, although somewhat more modestly. Yet as courts got a little breathing room, the rate of guilty pleas has not declined. Instead, in the federal system and some states, guilty pleas increased—usually from an already-high rate (as a share of total convictions) of 90 or 95 percent. To legal scholars who have examined plea bargaining for decades, this was not a surprise. Studies of courts in the 1970s found that plea bargaining did not decline even when caseloads for a local court system sharply fell, leaving prosecutors and judges with proportionately more time to handle the rest. Federal plea bargaining, it now seems clear, increased as prosecutors gained more bargaining leverage from mandatory sentencing laws and federal guidelines that greatly restricted judges’ sentencing discretion.

Plea bargaining, in short, is not simply of function of crime rates and the criminal caseloads that result from them. It depends many things: whether the parties want to reach a deal, strength of the evidence, and—far from least—how much bargaining leverage the law gives to prosecutors. To say merely that “plea bargaining is essential” begs the real question. It doesn’t answer whether all plea bargains we now achieve—95 percent in federal courts—are compelled by caseloads and strapped budgets. Plea bargaining may be essential, but how many—or what percentage of—cases must be resolved by guilty pleas rather than trials? Depending on local circumstances, courts and prosecutors might have the capacity—as most did 30 years ago—for 15, 20 or 25 percent of cases to go to trial.

The consequences of this reliance guilty pleas are not easy to determine. One worry is that plea deals are too much of a “bargain” and defendants get off too leniently, but that is hard to square with the fact the United States has by far the world’s highest imprisonment rate. Another concern is that some defendants are coerced into pleading guilty. That’s not hard to imagine when the post-trial sentence can be decades longer than the guilty plea sentence, and given that some defendants whose wrongful convictions were overturned based on new DNA evidence were convicted in the first place based on their guilty pleas.

On the other hand, the upside should be that court staffs are better able to handle the criminal caseloads they face. But even that advantage is not as certain or straightforward as it seems. That’s because there are reasons to suspect that the number of criminal prosecutions is not simply a result of the number of crimes and the number of criminals that police catch. It can also be a function of how much we plea bargain. Plea bargains, in other words, can indirectly add to caseloads at the same time that they help courts process cases more quickly.

The point is easiest to see through an analogy. Think of criminal cases as motor vehicles and courts as highways. Cars need roads, and—to be transformed into convictions—criminal charges need courts. When too many cars use the highways at once, traffic slows down and travel times increase. The “demand” for roads exceeds the supply. The same is true in courts overwhelmed by their caseloads.

An obvious solution in the highway context, it would seem, is to build more roads. Then road supply will meet the demand of local drivers. Having pursued that solution for decades in many places, however, cities have learned it often doesn’t work out as planned. When the government builds more roads, traffic congestion often returns to its previous, overcrowded levels. That’s because traffic—the number of cars—didn’t say the same as roadways increased. Instead, more drivers took advantage of new road capacity. This is such a predictable response that economists and regional planners call it “the law of highway congestion.” It is one example of the more general problem of “rebound effects”—a label that describes increases in something as a result of some policy that was intended to reduce it. More simply, this is a version of the Field of Dreams axiom: “if you build it, they will come.”

In economic terms—and in retrospect—this is easy to understand. More and better roads make driving more appealing. In effect, they make driving cheaper. All else equal, when the price for something declines, demand for it goes up—people buy (or use) more of it. That’s why it’s turned out to be very hard for highway construction to relieve chronic traffic congestion; better roads make driving more attractive. To reduce traffic, one needs to raise the cost of driving and reduce the appeal of driving. A few cities have done this with a “congestion tax”—a fee for driving within the city. Another de facto way to do it is simply to tolerate bad road congestion. There are still lots of cars on the road, but there would be even more if roads were bigger and better.

Does the criminal justice system have an equivalent to “the law of traffic congestion”? There are good reasons to worry that it does. The first step is to see that plea bargaining is a lot like building more highways. More precisely, it is the equivalent of building more courtrooms and hiring more judges and prosecutors. Guilty pleas enable courts to handle a lot more “traffic”—to resolve more criminal cases than they could through trials. Plea bargaining lowers the cost of adjudication.

The second step is to remember that, when the price of something goes down, demand usually increases. We buy more of a good or use more of a service when it is cheap, and plea bargaining makes it cheaper for governments for prosecute and convict. But why would the number of prosecutions increase, simply because judges and prosecutors can now handle more of them? Decisions to file criminal charges turn on many factors other than whether a crime was committed and police caught the perpetrator. Police exercise discretion about whom to investigate and arrest. Some of that discretion occurs at the level of local policy—“arrest in all cases of marijuana possession and public intoxication.” Much of it is exercised case-by-case. After police hand off an arrest or incident report, prosecutors also exercise a lot of discretion. For lots of reasons, prosecutors decline to prosecute anywhere from 30 to 70 percent of the cases that police present to them. Sometimes the evidence is sketchy. Sometimes policies disfavor pressing charges, or the most serious charges. First-offender and drug-user diversion programs are frequent alternatives to prosecution. So are civil remedies of various sorts, from paying off a bad check to paying civil fines to a regulatory agency.

Discretionary decisions play out differently when courts and prosecutors can handle more cases thanks to the efficiency of plea bargaining. If it doesn’t “cost” as much to charge and convict, it is more tempting to do so. Police know courts can process some additional petty offenses, and prosecutors know that they can handle more as well. This doesn’t have to be a conscious recognition in every officials’ mind, just as drivers don’t about how they would find ways to drive less if roads were fewer and more congested. Rather, plea bargaining helps to create a new set of norms or baselines—about how many cases prosecutors and judges ought to handle, about which defendants ought to plead guilty, and perhaps about which events deserve to be charged as crimes. Cases with evidence so weak that a trial conviction is highly uncertain now look worth the effort because, with hard-ball right plea bargaining, they can be turned into convictions. After years of achieving 95 percent of convictions through guilty pleas, a court system that suddenly had trials in 15 percent of cases would look like it is doing something wrong. The defendants who insisted on those additional trials would seem like ones whose cases didn’t “deserve” a trial and, consequently, that merit a harsher sentence because they had one.

All of these things are hard to measure. Empirical researchers have not yet demonstrated that plea bargaining actually drives up the number of cases in criminal courts. It may be the kind of phenomena that simply can’t be reliably measured. But beyond the compelling market-like logic that holds true in so many other contexts—as something gets cheaper, we use more of it—there is some suggestive evidence that a “law of traffic congestion” might operate in criminal justice systems.

For one, recall that criminal caseloads continue to increase long after crime began to decline in the early 1990s. More tellingly, Professor John Pfaff has found that evidence that, in many states, prosecutors file charges a higher percentage of cases they receive from police than they did twenty or thirty years ago. That is, they use their discretion less often to decline to prosecute. Reasons for this are unclear. Maybe police now collectively send prosecutors case reports backed by stronger evidence. Maybe the current generation of prosecutors has tougher-on-crime views than the previous generation did. But we ought to be concerned that we have made plea bargaining so common, and so efficient, that its effect has not simply been to enable the criminal justice system to process more cases without more judges and prosecutors. There is a good chance that plea bargaining has also increased the number of criminal cases in the system.

That might be good thing if crime was increasing. Or if we simply couldn’t afford to increase funding for prosecutors and judges at the same that we do for police and prisons. Or if we placed no social and political value on trial by jury. But none of that is true. What is true is that, as we have increased the rate of guilty pleas from already high levels of 75 or 85 percent of convictions to 90 or 95 percent, the United States also created the single most punitive criminal justice system, with by far the highest incarceration rate, in modern world history. That alone ought to be reason to worry that our exceedingly efficient system of plea bargaining has triggered “rebound effects.”