Violent crime did increase in the United States in 2016. But not everywhere.

Baltimore, Chicago, and St. Louis have all suffered a large increase in murders the past few years, while communities like Omaha, Austin, and Miami have seen crime go down.

There are many explanations for why crime increased in some cities but declined in others, including the opioid epidemic and gangs.

But there is another explanation for why some cities have seen large spikes in violent crimes: Their residents no longer trust the criminal justice system.

“There are any number of theories on what causes crime rates to swell, but nearly everyone agrees that public trust is essential to successful law enforcement,” Los Angeles Police Chief Charlie Beck wrote recently in the Los Angeles Times.

“Police alone cannot reduce crime. Community partnerships, joint problem solving, and open communication with the public are critical. When those links are weak, police are less effective, particularly at preventing crime.”

Beck’s wisdom is corroborated by a 2016 survey of more than 2,000 Americans. That study found that 81 percent of people with a high level of trust in police said they would definitely report a crime, compared to just 54 percent of people with low trust.

In other words, if a community does not believe its criminal justice system is fair, then it is far less likely to cooperate with that system. And when a community does not cooperate with law enforcement, crime goes up.

That is why I’ve co-sponsored three criminal justice reform bills—the Smarter Sentencing Act, the Sentencing Reform and Corrections Act, and the Mens Rea Reform Act.

The Sentencing Reform and Corrections Act of 2017 is a bipartisan bill that would eliminate mandatory life sentences for three-strike drug offenses, give judges discretion when sentencing non-violent drug offenders, and allow federal prisons to create more programs to reduce recidivism.

The Smarter Sentencing Act of 2017 would give judges additional discretion when sentencing nonviolent drug offenders and allows for more cases in which judges have to retroactively reduce sentences for nonviolent offenders.

The Mens Rea Reform Act of 2017 would require federal prosecutors to prove defendants actually had criminal intent when they violated a federal statute.

I would proudly vote for any of these bills, individually or packaged together, because I believe reforming our criminal justice system is good policy—and a moral imperative.

The United States has experienced a 500 percent increase in the number of inmates in federal custody since 1980. Almost 50 percent of those federal inmates are serving sentences for drug offenses.

Mandatory sentences, particularly drug sentences, can force judges to impose one-size-fits-all sentences without taking into account the details of individual cases.

Frequently, the results of these policies are lengthy sentences for minor nonviolent drug offenses that are far longer than the sentences given to criminals convicted of rape, assault, or even murder. These sentences disproportionately affect minorities and foster distrust of the criminal justice system.

We must safeguard the legitimacy of our criminal justice system by ensuring that the punishment fits the crime, while continuing to protect the public. Each of these bills is a step toward that ultimate goal.

If we can ensure that time given to criminals matches the crimes they commit, I am confident trust will be restored in our criminal justice system and crime rates will fall again.