Washington state constitution
Article II
Section 29

The labor of inmates of this state shall not be let out by contract to any person, copartnership, company, or corporation, except as provided by statute, and the legislature shall by law provide for the working of inmates for the benefit of the state, including the working of inmates in state-run inmate labor programs. Inmate labor programs provided by statute that are operated and managed, in total or in part, by any profit or nonprofit entities shall be operated so that the programs do not unfairly compete with Washington businesses as determined by law.