In a sign of how far the nation has moved from supporting solitary confinement for inmates, the leading organization for the nation’s prison and jail administrators on Wednesday called for sharply limiting or even ending its use for extended periods.

The statement from the Association of State Correctional Administrators, whose members are largely responsible for the growth in solitary confinement in recent decades, is its most forceful to date on the practice. Calls for reducing the use of solitary have taken on greater urgency since President Obama ordered the Justice Department in July to review its use in federal prisons.

A day earlier, California announced plans to overhaul its use of solitary confinement, including by setting strict limits on the prolonged isolation of inmates, as part of a legal settlement that is expected to sharply reduce the number of inmates held in the state’s isolation units.

Congress and more than a dozen states are also considering placing limits on the use of solitary confinement, which is used on tens of thousands of inmates each year as punishment or to protect them from one another, as well as to isolate prisoners with severe mental illnesses.