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Sentencing Laws and How They Contribute to Mass Incarceration

To fight for fairer sentencing, we first need to understand how the system works.

  • James Cullen
October 5, 2018

What factors decide how long someone spends in prison? The answer is, it’s complicated. If you care about criminal justice reform, the technical nature of sentencing makes it hard to understand the laws that determine the length of someone’s prison term — and even harder to understand how those laws might be creating unjust outcomes. 

Here, we explain a few of the most common terms you’re likely to hear in any debate around sentencing. We also give simple, clear-cut explanations of how, based on our research, those laws contribute to mass incarceration. There’s a lot more to know about sentencing law and policy. But this will give you a good start so you can join the conversation. 

Mandatory minimums 

A lot of the debate on criminal justice reform focuses on mandatory minimums. What are they and why do people — including us — think they’re unfair? 

Simply put, anyone convicted of a crime under a “mandatory minimum” gets at least that sentence. The goal of these laws when they were developed was to promote uniformity; it doesn’t matter how strict or lenient your judge is, as the law and the law alone determines the sentence you receive. 

Regrettably, the adoption of mandatory minimums has not led to a fairer system. In fact, it’s had the opposite effect. By tying judges’ hands, mandatory minimums effectively took power away from judges and gave it to prosecutors, who could threaten to charge defendants with crimes that would “trigger” a mandatory minimum. Facing a harsh sentence from which there’s no other escape, a defendant can often feel coerced into admitting their guilt — even sometimes falsely confessing.  

Interestingly, federal judges have come to dislike mandatory minimums, especially in drug cases. Mandatory minimums often apply to nonviolent drug offenders, forcing judges to harshly punish those who pose the least physical danger to communities. While the goal of mandatory minimums may have been fairness, they’ve instead caused an imbalance in the courtroom that has helped drive mass incarceration

While mandatory minimums have been in place in some states since the 1950s, their use grew after the 1984 Sentencing Reform Act, which added significant mandatory minimums for many federal crimes and abolished federal parole. States followed, and soon mandatory minimums became a standard response to drug epidemics and crime spikes. What started as a well-intentioned attempt to impose uniformity became too restrictive, creating new disparities and injustices in the process. 

Three-strikes laws

“Three-strikes” laws are another way legislatures have removed sentencing discretion that judges used to have. Under these laws, which started in California, a person is considered to be beyond rehabilitation after committing three crimes. As a result, once they’ve reached the “third strike,” the penalty is much more severe than it would usually be. Sometimes a life sentence can result from a combination of relatively minor offenses, just because the third strike requires the judge to impose a very long prison sentence. There are people today spending their lives in prison for committing three petty crimes

These punishments are inhumane and nonsensical, even from a public safety perspective. It costs money to keep people in prison, so a three-strikes law can result in the government spending $500,000 to incarcerate someone for committing three $500 crimes. 

And it’s unclear whether these laws even have the desired effect. The theory is that if someone knows they’ll face a serious punishment for their third offense, they won’t commit it — or won’t even commit their first offense. But it’s been shown that that’s not how people think, and it’s definitely not how people think about crime. In technical terms that means it’s unclear whether three-strikes laws have the desired “deterrent effect.” 

Truth-in-sentencing laws

If you’re sentenced to “10 years in prison,” you generally don’t spend 10 years in prison. That’s because the federal system — and most states — let people earn time off their sentence for “good behavior,” creating an incentive for people to improve themselves and turn away from crime while in prison. People also become eligible for parole, a type of early release after which a former inmate continues to be supervised by government officials. But parole has to be earned — again, giving people a reason to spend their time behind bars productively, on education or work programs. 

“Truth-in-sentencing laws” eliminate those opportunities for early release, requiring people to serve (for example) 75 percent of their prison term physically behind bars. The goal is to ensure that the sentence the judge imposes is what a person will actually serve in prison — in other words, “what you see is what you get.” 

That may seem like a reasonable goal, but eliminating early release options actually gives people less of an incentive to comply with prison rules or take advantage of education or training opportunities. It also means that there’s no way around prison sentences that are already too long.

Different sentences for different drugs 

Generally, possessing 5 grams of marijuana will earn you less prison time than possessing 5 grams of cocaine. The idea is that more dangerous drugs should be punished more severely. But that hasn’t always been the case. Crack and powder cocaine are chemically the same substance. But possession of crack cocaine, which is more common in communities of color, is punished much more severely than possession of powder cocaine, which is more common in wealthier white communities. While somewhat reduced, this disparity remains, even after the Fair Sentencing Act of 2010. 

What can be done? 

Now that you’ve learned about some of the more controversial sentencing decisions of the last 30 years, you can join the conversation about how to fix them. There are ways to restore fairness to criminal sentencing and help end mass incarceration in the process. You can read about them here and find the Brennan Center’s detailed analysis of how 40 percent of American prisoners are behind bars without any public safety justification here.