Criminal sentencing has been in the headlines a lot lately, ever since the Supreme Court’s recent decision in Blakely v. Washington put into jeopardy a system that has dramatically increased the safety of all Americans. Now there’s another threat looming over the tough but fair sentencing laws that determine how much time hardened criminals spend in prison. Ironically, these attacks are being marketed as “smart on crime.”

In reality, they are nothing less than a wholesale retreat from the fight to ensure American’s safety and that of our communities.

Over the past 20 years, Congress has approved tough but fair sentencing guidelines and mandatory minimum sentences for certain particularly heinous and dangerous crimes—preying sexually on children, using a gun to commit a violent crime, and drug trafficking—and for criminals who stubbornly continue to break the law despite repeated convictions.

These measures ensure that the worst criminals stay behind bars for meaningful periods of time, keeping them off our streets and away from our families, and making would-be offenders think twice about risking a long prison sentence.

What are the results? Since this common-sense sentencing policy was created, our families are much safer than they were in previous decades, and we can see the difference: crime in the United States is at a 30-year low. Look at it this way: if crime rates had stayed at 1993 levels, more than 27.5 million additional violent crimes would have been expected. The bottom line is that tough sentencing works.

That’s why mandatory minimum laws have repeatedly been enacted by Congress, why they are consistently supported by Presidents from both parties, and why tough sentencing enjoys widespread public support.

But now some critics are trying to have the laws that establish mandatory minimum sentences repealed. One of them, the American Bar Association (ABA), has recently advocated that state and federal mandatory minimum laws be discarded—in other words, that we go back to the failed policies of the high-crime past. The ABA argues that mandatory minimums aren’t cost-effective.

Critics claim that mandatory minimums unjustly impose long sentences on young, low-level offenders. They ignore the fact that Congress long ago created a “safety valve” provision that exempts low-level, non-violent offenders without a prior criminal record from the mandatory minimums. Even offenders who don’t qualify for this safety valve treatment can avoid a mandatory minimum sentence by cooperating with law enforcement’s investigation or prosecution of another offender.

Opponents also argue that “non-violent drug offenders” should be exempted from mandatory minimum sentences. This view simply ignores the pervasive violence and harm to society that invariably characterizes the market for illegal drugs. Drug trafficking is a leading cause of violence on American streets, and drug abuse destroys lives. In 1998 for example—by their own admission—61,000 convicted inmates had committed their crime to get money for illegal drugs, and fully a third of state inmates had committed their crime while on drugs. Drug offenders contribute to violence in a very real way.

Mandatory minimum sentences are a critical tool to protect our communities. During the 1960s and 1970s, America experimented with criminal justice innovations such as early release on parole, rehabilitation rather than incarceration, and wide judicial discretion to impose little or no jail time—the same policies the ABA now advocates. In the past, these policies failed miserably to prevent crime or promote safer streets. They would undoubtably fail again today.

Despite these recent attacks, the legacy of mandatory minimum sentences is clear: tough but fair sentences are taking habitual lawbreakers off the street, they are locking up the most dangerous criminals among us, and they are ensuring the safety of all law-abiding Americans. We need mandatory minimum sentences, and we must resist the currently fashionable, but misguided, calls for their repeal. It would hardly be “smart” to swear off the very instruments which have lead to America’s recent success in its fight against crime.

(Sandy Mattice is the United States Attorney for the Eastern District of Tennessee. His offices are in Chattanooga.)