Why are so many people in prison?

What state finds could help save millions in taxpayer dollars.

Ohio is planning COLUMBUS — a deep dive into crime data

— arrests, convictions, sentencing, probation, incarceration, behavioral health and more to help

— answer some vexing questions, such as why the state has such a high prison population and why so many people here are on probation? The answers — and what is done about it — could have a profound influence on the public, which spends millions of dollars every year on the state’s criminal justice system.

Number crunchers and policy wonks will spend nearly a year examining why Ohio struggles with high prison populations, increasing opioid overdose deaths and one of the highest rates of adults on probation in the country.

Data is collected locally by scores of agencies, departments, courts and more. Sorely lacking is the ability to comprehensively look at the information, said Sara Andrews, director of the Ohio Criminal Sentencing Commission.

“It is disparate. It is not standardized. Everyone keeps data, but there is no way to effectively bring it all together and talk about it,” she said.

Even a simple question — how much does Ohio spend on criminal justice each year? — can’t be easily answered, she said.

The goal of Justice Reinvestment is to have data-driven decisions on what programs to back, Andrews said.

The effort has the backing of all three branches of state government. Gov. John Kasich, Attorney General Mike DeWine, Ohio Supreme Court Chief Justice Maureen O’Connor, House Speaker Cliff Rosenberger and Ohio Senate President Larry Obhof jointly requested support from the U.S. Department of Justice and The Pew Charitable Trusts to address criminal justice system challenges.

The Council of State Governments will help Ohio collect data to analyze statewide criminal justice trends, including a drop in violent crime but increase in murders and assaults, a decline in arrests for murder and assault, an increase in opioid overdose deaths.

CSG will also look at how and why the state has more than 240,000 adults on probation in 2015 — ranking Ohio third among states for probation rates.

Meanwhile, Ohio’s prison population remains stubbornly high even though the number of people sent to prison has declined.

Andrews said the examination will look at behavioral health data and how it fits with the criminal justice system.