The official marker plaque:
The Stockton Developmental Center was established in 1853 as the Insane Asylum of California, the first of several state asylums. Stockton's founder, Charles M. Weber, donated half of the 100 acre site. It was one of the first facilities of its kind in the western U.S. and played a major role in developing California's mental health system. In the early 1970's, the focus of the center shifted from treating patients with mental disabilities to training people with developmental disabilities. This served to spearhead the movement to provide services outside the institutional setting. The Stockton Developmental Center was closed in 1996.
Historic homes that housed doctors and staff are located in the adjacent historic district.