Studies of the criminal justice system rarely consider what happens after insanity defendants are freed. In Oregon, that has meant state leaders have had no objective measure of the state’s approach, which places more people into community treatment and frees them from state supervision more quickly than other states.

The Malheur Enterprise and ProPublica calculated outcomes by reviewing public records collected from the Psychiatric Security Review Board, courts and state agencies. The analysis is among a handful of recidivism studies of insanity defendants, experts said.

Reporters searched available electronic court records for all 334 people freed by the review board from 2008-17. Because digital court records in Oregon are incomplete before 2016 and because not all states were searchable online, the analysis likely understates the number of new crimes committed.

People’s identities were confirmed by birthdate or matching the original insanity case to a person later charged with a new crime who shared the same state offender ID. Often, both were available to match.

We then looked at what happened during the three-year period after people were released, the standard approach among scholars. Of the 334 people freed between 2008-17, that period could be examined for 220 of them.

About 35 percent, or 76 people, were criminally charged again within three years. An additional 18 people committed new crimes after that period.

Most often, people freed after being found not guilty by reason of insanity were back in criminal court in little more than a year. Many appear to have become homeless shortly after leaving the state’s supervision, even though housing is identified as a primary need when they are discharged.

They were charged with felonies about as often as people freed after serving prison terms — both 16 percent — according to our analysis and the Oregon Department of Corrections. Experts said that matches research studies finding little evidence that mentally ill people are more likely to commit violent crimes.

One researcher studied rearrest rates among Oregon insanity defendants in 1986. The analysis, published in the International Journal of Law and Psychiatry, was done by Dr. Joseph Bloom, a forensic psychiatrist who once served as dean of medicine at Oregon Health & Science University and has been president of the American Academy of Psychiatry and the Law.

His results paralleled those found by the Enterprise-ProPublica analysis.

Bloom searched for criminal records in an Oregon police database that is not available to the public but that is regularly used by the review board to monitor clients. In 1982, he tallied the new arrests of 144 people freed from state supervision from 1978-80. He found that 42 percent had been arrested within 18 months and that 16 percent were arrested for felonies.

A more recent study looked at Connecticut, which is one of three states with a Psychiatric Security Review Board similar to Oregon’s.

Dr. Michael Norko and five other authors tracked the recidivism of 215 people freed by that state’s board between 1985 and 2015. They found that 16 percent were later re-arrested, with about a third of those being for felony crimes, according to the article published in the Behavioral Sciences and the Law.

“Given the significant commitment of resources in the state devoted to the PSRB’s supervision, monitoring, and community support of acquittees, these results have important policy and public safety implications,” the authors wrote.