The IDD at Napanoch was the first institution of its kind in the world, created -- after persistent lobbying -- in the faith that it was a progressive action that would remove dangerous defectives from the streets of NY. There was considerable curiosity about the techniques and effectiveness of the new institution. Walter N. Thayer, Jr., M.D., the IDD's first superintendent, was to become nationally known . . . .

Thayer called his program The Napanoch Plan. "Forty to fifty percent of all prison inmates", he said, 11 are mental defectives." Their defectiveness, usually from birth as a result of bad heredity, cannot be changed; their delinquency, however, resulting from faulty training during the formative years and "vicious habit formation," is capable of treatment and reversal. "So fill the life with good habits as to leave no room for the bad," he advised, and prescribed a program of "strict but kindly discipline" and the methodical use of positive as well as negative reinforcements.

On admission to Napanoch, the new inmate would be individually studied for about 10 days, including physical and mental examination, treatment of any medical problems, and determination of a program of training to realize his "possibilities." The inmate's responsiveness to the training program would dictate his daily living circumstances. Higher functioning inmates were expected to progress from cell housing to dormitories to individual rooms, and then to living in the farmhouse outside the prison walls. The final step was parole, with a gradual decrease in the degree of supervision as the inmate demonstrated his ability for responsible "self-supervision."

The indefinite one-day to life sentence allowed authorities to reverse the mechanism at any time. The average stay in the institution was two and a half years, but the threat of parole revocation was seldom removed: contrary to the policy of the state prisons, Thayer said, "the practice at Napanoch is to issue no absolute discharges."