Tiffany West, 21, right, leans on Jamika Smallwood, left, while attending a candlelight vigil for homicide victim Wesley West in the Congress Heights neighborhood of Washington, D.C. (Photo by Amanda Voisard/For The Washington Post)

The right-left alliance on criminal justice seems to be breaking apart. Sentencing reform is stalled in the Senate. Conservative commentators are pronouncing ominously about a phantom crime wave. Donald Trump's old-fashioned, tough-on-crime presidential campaign is a smashing success.

In fact, there was never much of a consensus to begin with. Policymakers on both sides of the aisle were starting to give up on the law-and-order rhetoric that was typical 20 years ago, when a crime wave combined with new, more stringent sentencing laws to sharply increase the incarcerated population. Yet the shift was largely superficial, not substantive. Policymakers never really confronted the compromises and political risks involved in a shift in crime policy.

Meaningfully reducing the number of Americans behind bars would have required shorter terms for violent offenders. That's something President Obama and other policymakers never suggested, probably because they suspected that the public's views on public safety hadn't changed all that much even after two decades of plummeting crime rates.

If that was the calculation that elected officials were making, Trump is proving them right.

"We're going to get rid of those gang members so fast your head will spin," the GOP frontrunner and real-estate magnate said last month. Trump did not offer details.

In any case, as Michael Grunwald reports in Politico, Trump's rivals are following suit. Sen. Ted Cruz (R-Tex.) said Obama, who delivered a major speech on criminal justice in Philadelphia in July, was partly at fault for violence against police officers.

"They're feeling the assault from the president, from the top on down as we see — whether it's in Ferguson or Baltimore — the response of senior officials of the president, of the attorney general, is to vilify law enforcement," Cruz said.

Meanwhile, on Capitol Hill, aides are still working on a bill to reduce sentences for criminals who do not commit violent offenses.

As The Washington Post's James Hohmann and Elise Viebeck report, there isn't yet agreement on how to classify violent and nonviolent offenders. Distinguishing between the two is harder than it might seem: A 60-year-old convicted of multiple armed robberies as a young man might be less likely to commit violence after leaving prison than a 21-year-old in for dealing drugs who has no violent criminal history but no job prospects, either.

Lawmakers' caution on this issue is another suggestion that they are sensitive to public perceptions of leniency. Further complicating the politics of the bill is speculation in the press that a violent crime wave is building nationwide.

As Wonkblog has reported previously, that crime wave could be real, but it's yet to show up in the available data. Judging by the number of homicides in the country's 10 largest cities, the current year is on pace to be the third safest year for urban residents at least since 1985. Crime is up sharply in some cities, particularly in Baltimore, but it is not clear whether patterns in those cities are connected to one another or to national trends.

[Read more: I went looking for the uptick in murders. Here's what I found.]


Lawmakers haven't even broached the topic of reducing sentences for violent offenders. There aren't all that many inmates incarcerated for nonviolent crimes, and analysts predict that large reductions in the prison population will require a new approach to violent crime as well.

For example, as this forecasting calculator from the Urban Institute shows, cutting the average nonviolent offender's time in prison in half would reduce the prison population by less than a quarter over the next six years.

To be sure, the actions that federal policymakers have taken so far may be small, but they're no less important for the affected inmates and their families. The Sentencing Commission, a bipartisan agency of the judicial branch composed of judges and legal scholars appointed by the president, issued new guidance to the courts on sentencing drug offenders last year. Many new convicts will receive shorter terms, and about 46,000 current inmates are eligible to petition for early release. Obama has also commuted the sentences of 46 federal offenders.

[Read more: Obama commutes prisoners' sentences]

However controversial the issue is in Washington, most of the responsibility for setting criminal justice policy rests elsewhere. There are more than 2 million inmates behind bars in the United States on any given day, and federal prisoners make up only about one in ten.

State policymakers such as Bruce Rauner, the Republican governor of Illinois, are still committed to reducing their prison populations. Local officials can also limit incarceration without damaging public safety by reforming local jail administration and giving cops alternatives to making arrests when they encounter nonviolent, habitual lawbreakers on the street.