First, here is the link to a training module developed in the mid-1990s to help police respond more appropriately in situations that involved people with developmental disabilities.
The document is quite large. If you aren't able to download it, work backwards to the government's URL, www.eric.ed.gov and search on "police training and developmental disabilities."
I know the people who put this unit together and they did top notch work.
Stay tuned. More resources to come.