The HALT Act would bring New York’s system more into line with international humanitarian standards. Inmates could spend no more than 15 consecutive days in any type of segregated confinement, or 20 total days over the course of 60 days. Currently, inmates can be moved out of special housing units but remain in isolation in other types of units or in their own cells — a practice known as keeplock.

The act also would establish alternative rehabilitative measures, including special “residential rehabilitation units”; prohibit confining vulnerable populations to solitary; improve conditions in solitary; beef up reporting rules; and enhance due process protections.

These reforms have been a long time coming. The HALT Solitary Campaign took root in 2012. Since then, its reforms have gradually gained steam and political support. Advocates say an earlier version of the bill looked as though it might pass in 2019, but Mr. Cuomo expressed concerns about the costs of implementation. Last November, the Partnership for the Public Good released a report showing that state and local governments would in fact realize an estimated $132 million in annual savings from reduced facility costs, reduced medical costs and lower lawsuit expenses. Reformers are optimistic that the bill’s time has finally come.

Read the full letter on the New York Times website here.