The law, like a pendulum, sometimes moves from one extreme to another. For most of the 20th century, Congress gave federal judges wide discretion to select the punishment to be given to a particular defendant in a case. Typically, lawmakers set a maximum on the range of applicable penalties, such as “no more than five years’ imprisonment.”

Beginning in the 1980s, Congress went in the opposite direction. Lawmakers adopted several statutes with mandatory minimum punishments. Federal judges had to impose those minimum penalties upon conviction, regardless of any mitigating circumstances present in a specific case. Sell X grams of cocaine, and you get at least Y years in prison.

Each approach has problems. If you give judges complete discretion, sentences will likely vary widely across the nation. Federal judges in Maine may sentence differently than their counterparts in Hawaii. That disparity is undesirable in a system that promises uniformity. If you mandate that judges impose specific minimum sentences, sentencing disparities will be reduced (albeit not entirely), but judges in Minnesota and Texas may find that sentences imposed on particular defendants are unjust because they are unduly harsh.

Congress is now reconsidering some of our sentencing laws, this time with an eye to deciding whether it should eliminate mandatory minimum sentencing laws altogether, or just modify them slightly. Different considerations are driving this re-examination (and likely motivate different members). The number of federal inmates — and the cost of imprisoning them — have skyrocketed since the 1980s, and there are a goodly number of cases where the mandatory minimum sentences seem exceptionally severe.

Deciding upon the most appropriate sentence for each particular offender is far from easy. Supreme CourtJustice Felix Frankfurter once wrote that “no more difficult task confronts judges than the determination of punishment not fixed by statute.” Sentencing forces judges to predict what will happen years later. Will imprisonment turn someone into a hardened criminal? How many years can a person be imprisoned before that happens? Federal judges do the best that they can when making those decisions, and there is no reason to assume that they will do a poor job.

Deciding where to draw the Goldilocks line between complete discretion and no discretion involves imponderables that professionals have debated for decades. Even professionals find it difficult to craft sound sentencing policy. And no politician wants to be tarred with the dreaded “soft on crime” label, because everyone fears seeing that label used by an adversary in a 30-second commercial come Election Day.

For 50 years, the two parties have tried to outbid each other for the mantle of Law and Order Hero. They have increased the maximum sentences that judges may impose and required judges to impose mandatory minimum sentences on certain offenders, such as relatively small-scale crack cocaine traffickers. Meanwhile, there has been little discussion of the assumptions underlining this approach.

For example, do mandatory minimum laws actually have a deterrent effect? And there’s an even larger question: Do we have enough investigators, prosecutors, public defenders, judges and support personnel to make the criminal justice system function well? Members of Congress have been happy to amp up criminal penalties in the hope of persuading the public that they have done something to fight crime. But unless and until we get answers to these larger questions, we have no way of knowing whether inflexible and ever-harsher penalties are effective crime-fighting tools, ineffective, or maybe even counterproductive.

We now have the opportunity to change the way that the debate has been conducted. Organizations on the right and the left — the Heritage Foundation and Families Against Mandatory Minimums, to name just two — have urged Congress to reconsider and soften the harsh effects of some of the mandatory minimum laws now on the books. There is disagreement as to how reform should be done. But there is unanimity that the public deserves a sober, serious debate over the issue. Congress should do just that.

 - Paul Larkin is a Senior Legal Research Fellow in the Heritage Foundation’s Edwin Meese Center for Legal and Judicial Studies.