As Virginia lawmakers continue to battle over the state budget, they are overlooking a billion-dollar issue.

The executive budget that lawmakers have been debating since January projects that Virginia will spend more than $1 billion on prisons and corrections by 2015 — a threshold the commonwealth has crossed only once before. Also, in January, lawmakers learned that, after several years of flat or declining numbers, Virginia’s prison population has increased for the first time in five years.

With these worrisome trends, you would think that Richmond would be springing into action. Instead, a series of smart-on-crime measures similar to those in other states was scuttled this session. It is time for serious discussion of these issues, before more money is wasted on policies that don’t work.

A Justice Policy Institute report published this month shows the effect of the current course: Instead of Virginia tax dollars supporting health care, schools and roads, that money is increasingly going to incarcerate people who could be safely managed in the community.

Since the 1970s, the commonwealth has experienced an increase of more than 700 percent in its prison population. By 2007, 1 in 89 residents was incarcerated. Billions of dollars have been spent over the past two decades building prisons and jails.

How did Virginia get on this treadmill?

First, because of changes by lawmakers in the 1990s, more people are serving longer sentences. Under a set of changes known as “truth in sentencing,” the possibility of parole was eliminated for most people, and the amount of time inmates could have shaved from their sentences for working, getting treatment and behaving well was curtailed. Lawmakers also enacted mandatory minimum sentences, taking discretion out of the hands of judges.

About a quarter of such mandatory minimums apply to drug offenses. At a time when there has been widespread recognition of the failure of the “war on drugs” and a reconsideration of sentencing and drug policy in a number of states and in Congress, drug arrest rates in Virginia are on the rise, surpassing the U.S. average.

Further, among the small group of individuals still eligible for parole in Virginia, few are actually paroled. While a law allows for the compassionate release of older and ill prisoners — a group that can cost as much as five times to incarcerate as a younger prisoner, mainly due to health-care costs — few are released through this mechanism, either. In many ways, Virginia’s prisons are functioning as expensive nursing homes.

Finally, it is important to note costs that are imposed outside prison. More arrests mean that more people carry the burden of a criminal conviction after they are released. While the state should be commended for taking some steps to restore the right to vote to some felons, hundreds of thousands of people with records still face barriers to getting jobs, finding housing or receiving public benefits — a series of hurdles that make it more challenging for people returning to the community to move on to crime-free lives.

Unsurprisingly, these poor policy choices do not impact Virginia communities equally. African Americans compose 20 percent of Virginia’s population but make up 60 percent of those in prison and 72 percent of those there for a drug offense. In Virginia’s largest counties — including Fairfax, Prince William, Loudoun and Arlington — African Americans are arrested for nonviolent drug possession at much higher rates than their representation in the community. This occurs despite the fact that research shows African Americans and whites use drugs at roughly the same rates.

This picture can change. Virginia should follow the lead of other states that are safely and smartly reducing reliance on incarceration, bringing down prison costs and promoting fairer and more effective policies. Virginia is trailing states such as Georgia, Mississippi, Oregon and Illinois that took steps on a bipartisan basis in the past year to reduce the impact of mandatory minimum sentences, reform parole practices, increase earned-time opportunities or reform “truth in sentencing.”

Rather than miss more opportunities to curb Virginia’s billion-dollar corrections budget, lawmakers need to reconsider the state’s sentencing and corrections policies through a cost-benefit lens to get a better fix of their impact on public resources, communities of color and public safety.

The writer is executive director of the Justice Policy Institute. From 2005 to 2010 he served as general counsel, chief of staff and interim director of the D.C. Department of Youth Rehabilitation Services.