Backers of a bill that would limit the use of solitary confinement in Maine prisons did not get most of what they wanted this legislative session.

Their bill, sponsored by Rep. Jim Schatz, D-Blue Hill, would have prohibited the prolonged use of isolation for prisoners with mental illness. Instead, what passed is a directive to the Department of Corrections to review the policies that could end with a prisoner in solitary confinement.

That review could point to ways in which the state could tighten up its regulations so that prison officials can maintain security without doing harm to the mental health of prisoners.

A growing body of opinion in the scientific world is finding that long-term isolation can cause permanent brain damage. In the eyes of many around the world, excessive isolation is seen as torture. It is particularly dangerous for people with underlying mental illnesses that they or prison authorities may not be aware of.

Schatz’s bill was supported by a variety of groups, including the Maine Association of Psychiatric Physicians, the Maine Psychological Association, the National Alliance on Mental Illness, church organizations and civil libertarians, such as the Maine Civil Liberties Union.

The important point these groups make is that inhumane treatment of prisoners comes with a cost. The rest of society pays when they are released, and almost all prisoners are released. That includes the 43 prisoners who were sent from the Maine State Prison’s special management unit directly to the street in the last two years. The directive is a good start, but it should not be the end of action on this issue.