Twenty years ago this week, President Bill Clinton signed into law the Violent Crime Control and Law Enforcement Act of 1994. It put more cops on the streets, imposed tougher prison sentences, and increased funding for prisons. The thinking was that harsher prison sentences could act as a deterrent to violent crime.

But by the time the bill passed, the nation's violent crime rate had already begun its long-term downward slide. The new law was attempting to solve a problem that was already being solved.

"We have to look in the mirror and say, 'look what we have done'"

What the law did do is help increase America's already-rising imprisonment rates — and, along with other laws from the tough-on-crime era, it did so in a way that punished minority groups much more than their white counterparts.

Jeremy Travis, president of the John Jay College of Criminal Justice, attended the bill's signing and later joined Clinton's Department of Justice. Since then, he's acknowledged the Clinton administration made some serious errors.

"We now know with the fullness of time that we made some terrible mistakes," Travis told NPR. "And those mistakes were to ramp up the use of prison. And that big mistake is the one that we now, 20 years later, come to grips with. We have to look in the mirror and say, 'look what we have done.'"

1) The law increased imprisonment, even as crime was already dropping

The chart above, from a fantastic report by the National Research Council, shows the crime rate, including homicides, had already peaked and began dropping even before the Clinton-era crime law passed and took effect. There are many possible reasons for that, including an aging population, less lead in the environment, and an improving economy.

But one of the reasons almost never cited for the dropping crime rate is the deterrence of imprisonment. Some criminologists, in fact, argue that harsher prison sentences may have made it more difficult to punish people. Vox's Dara Lind explains, "Criminologist Daniel Nagin has proposed that prison time may not be viewed by potential criminals as a severe enough punishment anymore. When more and more people are imprisoned or have been in prison, the social stigma of prison goes away — making it an ineffective deterrent."

2) America's imprisonment rate is higher than Russia's

One of the things America is truly best at is incarcerating people at huge rates. The National Research Council's report shows that the US has considerably higher imprisonment rates, when controlling for population, than any other country.

This trend persists when looking at individual states. Even America's most liberal states imprison more people than a huge majority of other countries around the world, according to an analysis from the Prison Policy Initiative.

3) Minorities are sent to prisons at far higher rates

Even before Clinton's crime law, black people were already facing a massive spike in imprisonment rates compared to whites — in large part because of the ramped-up war on drugs, which already encouraged state and local law enforcement to go after drug offenders. By increasing police presence and pushing more people to prisons with a goal of cracking down on violence, Clinton's crime law helped expand the war on drugs and further encouraged police to go after urban populations involved in the drug trade.

The National Research Council's report explains that some of this is due to higher rates of criminal offenses and victimization among minority communities, driven in part by similarly "higher rates of poverty and urbanization and a younger age distribution" within those groups.

But in many cases, minority populations aren't actually more likely to commit the crime they're locked up for. Black Americans aren't, for example, more likely to to use drugs or sell them than white Americans, but black people are much more likely to be arrested and incarcerated for drug offenses.

To make matters worse, the disproportionate arrests and imprisonment rates may exacerbate factors that lead to more crime. A study published in the journal Sociological Science found boys with imprisoned fathers are much less likely to possess the behavioral skills needed to succeed in school by the age of five, starting them on a vicious path known as the school-to-prison pipeline.

The policies are changing



In the past few years, all levels of government, pressed by recession-weakened budgets and the increasing costs of mass imprisonment, began to rethink their anti-crime policies.

A huge majority of states, for example, in the past few years passed sentencing reform that reduced certain punishments for some offenses, particularly nonviolent drug offenses, and expanded and reformed probation and parole as alternatives to imprisonment.

"it comes with human and moral costs that are impossible to calculate"



More recently, the federal government, particularly the Obama administration, has pushed reforms that will make it so fewer people, particularly nonviolent drug offenders, end up in prison. Even the Office of National Drug Control Policy, which heads the country's war on drugs, claims it's going to focus more on treating drug use as a public health issue instead of a criminal justice issue, although a significant chunk of its drug control budget will continue going to law enforcement efforts as well.

In a 2013 speech, US Attorney General Eric Holder touted the reasons on this list — the high imprisonment numbers, the racial disparities — to justify the Obama administration's reforms.

"As we come together this morning, this same promise must lead us all to acknowledge that — although incarceration has a significant role to play in our justice system — widespread incarceration at the federal, state, and local levels is both ineffective and unsustainable," Holder said. "It imposes a significant economic burden — totaling $80 billion in 2010 alone — and it comes with human and moral costs that are impossible to calculate."

The reforms, particularly on the state side, seem to having some effect. In 2009, the prison population began to decline for the first time in decades.

That doesn't mean America's mass incarceration problem is anywhere close to solved. But it is a sign that, two decades after the nation's leaders passed yet another misguided tough-on-crime law, the landscape is changing.