Crime, to the liberal, is never the fault of the perpetrator.

It’s the fault of society. Guilt lies with the criminal’s parents, his lack of a good education, poverty, drugs, or maybe feeling deprived because he never had the opportunities he deserved. As a consequence, punishment, particularly locking people up for doing bad things, is wrong; instead, every criminal needs rehabilitation. A true liberal would shut down the prisons – leaving enough open to house crooked business executives, polluters and climate change deniers – and designing government programs to rehabilitate the rest of the inmates.

That wouldn’t fly in today’s world, so the liberals have done the next best thing: hijack “criminal justice reform,” an idea high on many conservatives’ agenda, and adding to it a large reduction in the prison population by shortening the sentences of tens of thousands of felons. And, as they so often do, they have attached buzz words to their effort, buzz words which too many well-meaning conservatives have swallowed – hook, line and sinker.

Like “mass incarceration.” Federal prisons are, they claim, overflowing with “first-time, non-violent drug offenders” caught up in the criminal justice system and imprisoned, unfairly, for years. While in prison, we are told, the families of wrongly incarcerated offenders are torn apart. They claim that the bulk of these nearly-innocent offenders are African-Americans, showing the criminal justice system to be a racist operation.

All of those assertions are wrong.

“Mass incarceration” is a myth. It is what the U.S. government did to Japanese-Americans during World War II – people were rounded up and thrown in prison because of who they were, without any sort of trial or due process. Today, each resident of the federal prison system is there because he or she was arrested for committing a felony, pled guilty or was convicted by a jury or judge, was sentenced by a judge, appealed the sentence (or chose not to) to U.S. appellate courts and was subject to all the rights of due process provided by the U.S. Constitution.

The idea that federal prisons are overflowing with non-violent or minor drug offenders is also flat wrong. According to the Bureau of Justice Statistics, almost all – 99.5 percent – of drug offenders in federal prison are serving sentences for drug trafficking – which does not mean simply selling small amounts of marijuana or even heroin.

According to the U.S. Sentencing Commission, in FY2014, only 0.9 percent of all federal drug offenders received a sentence for “simple possession,” and most of these convictions were likely plea-bargained down from trafficking charges. Further, according to the U.S. Sentencing Commission, as of December 2014, there were 305 offenders serving a federal prison sentence for “simple possession,” of which 95 percent were non-citizens – meaning only 15 U.S. citizens were serving federal sentences for simple possession, and many, if not all, likely involved more serious charges that were pled down.

The assertion that the criminal justice system is racist, or even that minorities are mistreated and over-represented in the prison population, is also just nonsense. Fewer than 35 percent of state and federal prison inmates are African-American, (they are about 13 percent of the U.S. population). No criminologist will deny that African Americans have a proportionally higher rate of serious criminal offense than whites. In fact, according to FBI data reported by the Bureau of Justice Statistics, black offenders were responsible for over half of all homicides in the country between 1976 and 1995, and for over 60 percent of all robberies. African-Americans are both responsible for, and the victims of, the bulk of murders in the US: between 2000 and 2014 blacks were victims of murder eight times as often as whites per capita, nearly always as a result of black killers. According to Barry Latzer, Professor Emeritus of criminal justice at NYU, in a recent article in the Wall Street Journal:

Serious crimes are the main driver of African-American incarceration. The latest BJS figures, from the end of 2013, show that 57 percent of blacks in state prison were convicted of violent crimes. Only 16 percent were in for drug crimes. Those numbers nearly match the figures for the state prison population overall… Nor have blacks always served longer sentences than whites once incarcerated. In 1993, at the peak of the prison buildup, blacks and whites in state prison served identical terms, a median 12 months, for all offenses. For drug crimes, whites actually served slightly more time than blacks, 12 months to 11 months.

Too many conservatives, invested heavily in the idea of reforming the criminal justice system, have gone along with the liberal effort to return serious chronic felons to the streets. There is no question that there are plenty of problems with the criminal justice system and that the reform effort is legitimate and well-intentioned. Congress has over-criminalized the laws, many laws do not include a requirement for mens rea (a guilty mind, or intent to commit a crime), and often, particularly under state law, low-level offenders are incarcerated who would not be, to name a few.

But legislation pending in both houses of Congress would reduce many mandatory minimum sentences imposed for serious crimes, many committed with a firearm, often involving chronic, violent offenders. It would also retroactively reduce sentencing provisions of The Violent Crime Control and Law Enforcement Act of 1994, signed by Bill Clinton, which resulted in the conviction and imprisonment of thousands of violent criminals. The result would be to retroactively reduce penalties for thousands of serial armed career criminals including carjackers, bank robbers and kidnappers, reduce penalties for repeat high-level drug traffickers and weaken tools used by federal prosecutors to dismantle drug trafficking organizations.

Over the past several years, the U.S. Sentencing Commission has ordered the release of thousands of serious criminals from federal prison, and in 2014 reduced the guidelines for all drug traffickers, regardless of the type of drug, criminal history, history of violence, gang or cartel ties making over 46,000 convicted drug traffickers eligible for early release. It is estimated that the bills now pending in Congress could make another 12,000 eligible for early release.

There is no question that if these criminals are released from prison many will commit many more crimes. Recidivism rates for chronic drug traffickers are often over 75 percent – in other words, as many as three quarters will be arrested again for committing serious, often violent crimes. Worse, for every arrest, such criminals commit, on average, twelve other unsolved crimes.

House Speaker Paul Ryan wants to pass the House bill as soon as he can, and several Republican Senators, including John Cornyn of Texas and Chuck Grassley of Iowa are pushing to get the bill to the Senate floor (although several Senate Republicans, including Tom Cotton of Arkansas and Jeff Sessions of Alabama are deeply opposed). Even the Republican National Committee, adding to its record of brilliance on national election matters, at its recent spring meeting, unanimously voted to endorse criminal justice reform. Both houses have reported bills from the Judiciary Committees; to his credit, Senate Majority Leader Mitch McConnell has voiced skepticism about bringing the bill to the Senate floor. Some revisions have been made by the Senate bill’s sponsors, which may make it somewhat more palatable, although many problems still exist.

Virtually every Democrat in the House and Senate supports the bills, and Obama has called the legislation a legacy of his administration and the centerpiece of his second-term domestic policy agenda.

One thing is sure: the country will not be improved by freeing several thousand violent felons from prison, allowing them to wander free to continue their drug trafficking and violence against innocent victims.

Mr. Regnery is Chairman of the Law Enforcement Legal Defense Fund.