A few years ago the Dayton Art Institute experimented with using community
service labor, mostly in groundskeeping as I recall.  You could try
contacting them.

>For a possible session at next year's Midwest Museums Conference annual
>meeting, I would like to hear from anyone with experience using any kind
>of prison labor (community service, work release, adults, juveniles,
>etc.) in museum operations.  I am curious about how extensive the
>practice currently is, what applications it is notably effective or
>ineffective at, and whether--given current trends in both museum funding
>and in the costs of correctional systems--prison labor may become more
>common in the years ahead.  Please reply either directly or through the
>list.