29 USC 1844 - Compliance with written agreements

(a) Applicability to contracting activity or worker protection 
No farm labor contractor shall violate, without justification, the terms of any written agreements made with an agricultural employer or an agricultural association pertaining to any contracting activity or worker protection under this chapter.
(b) Statutory liability 
Written agreements under this section do not relieve a person of any responsibility that such person would otherwise have under this chapter.