The leaders of more than a dozen Middlesex County law enforcement agencies, including Arlington's, announced they have formally joined the White House-led Data-Driven Justice Initiative (DDJ), focused on reducing the number of mentally ill individuals awaiting trial in local jails.

The effort was launched last June to support communities who want to use data to be smarter about diverting people with mental illness away from the criminal-justice system and into community-based treatment, U.S. Chief Data Scientist D.J. Patil said in a news release Thursday, Oct. 13.

 "We are excited that DDJ has grown to include over 120 diverse communities across the country, reaching more than 90 million individuals," he said.

Nationwide, 64 percent of those being held in local jails suffer from mental illness, while 68 percent have a substance-use disorder.

Announcing their participation today are the Middlesex Sheriff’s Office and police departments in Arlington, Ashland, Bedford, Billerica, Boxborough, Cambridge, Chelmsford, Dracut, Lowell, North Reading, Reading, Tewksbury and Watertown. The Holliston, Hopkinton and Sherborn departments will also participate through collaboration with Ashland.

"Police-led diversion programs have shown remarkably success and continued promise as municipal police officers address the challenges of mental illness and addiction," Chief Fred Ryan said in the release. "By diverting these vulnerable members of our communities in the appropriate programs instead of jail cells, we lesson the strain on the criminal justice system while giving people the best possible chance to retake their lives.

The announcement came as President Obama was in Pittsburgh for the White House Frontiers Conference, which is focusing in part on DDJ and disrupting the cycle of incarceration. DDJ seeks to reduce unnecessary pretrial incarceration by enhancing the use of new and existing data, and by helping spread best practices.

"The Obama administration's emphasis on diverting low-level offenders away from incarceration and toward treatment could not have come at a more crucial time for our office. The DDJ initiative will provide resources to better safeguard our communities, while increasing public safety by getting people the community-based care they need."

Middlesex Sheriff Peter J. Koutoujian said: "Today, 46 percent of those entering our custody report a history of mental illness and 75 percent of those under the care of our mental health staff also suffer from a co-occurring substance use disorder."

Bedford Police Chief Robert Bongiorno, a former Arlington captain, said: "Here in Middlesex County, we are very fortunate to have law enforcement agencies that work closely and progressively on issues that affect our community members. Here in Bedford, we have worked closely with the Middlesex County Sheriff’s Office and our neighboring cities and towns to put forward initiatives that will make a real difference in the battles against mental illness and substance abuse. I am proud that the White House is committed to this mission."

Cambridge Police Commissioner Christopher J. Burke added: "We are proud to be among the participating law enforcement agencies in Middlesex County and New England leading the way in this important work. By joining both the Data-Driven Justice and Police Data initiatives, the Cambridge Police Department remains committed to increasing its transparency with data, policies, and procedures and advancing the innovative solutions we offer with our community partners to best serve vulnerable populations."

This announcement was published Thursday, Oct. 13, 2016.