(a) Unless otherwise required by law, each governmental entity within this state that contracts for public works construction shall ensure that neither the awarding governmental entity nor any agent responsible for procuring a contract directly between the governmental entity and a contractor shall not:

(1) Require any bidder, contractor, subcontractor or material supplier to enter into or agree to enter into any prehire agreement, project labor agreement, collective bargaining agreement or any other similar agreement with one or more labor organizations on the same or other related construction projects; or

(2) discriminate against or treat differently any bidder, contractor, subcontractor or material supplier for becoming, refusing to become or remaining signatories or otherwise to agree to enter into any prehire agreement, project labor agreement, collective bargaining agreement or any other similar agreement with one or more labor organizations on the same or other related construction projects.

(b) Nothing in this section shall prohibit:

(1) Any bidder, contractor, subcontractor, construction manager, design-builder or material supplier of any tier from voluntarily entering into agreements described in paragraph (1) of subsection (a); or

(2) any contractor, construction manager or design builder from requiring its subcontractors or material suppliers of any tier to enter into a collective bargaining agreement.