The employer and representative of the employees shall bargain collectively, which for the purposes of this chapter means performing the mutual obligation to meet at reasonable times and confer in good faith with respect to all matters bargainable under the provisions of this chapter. The failure or refusal of either party to agree to a proposal; to change or withdraw a lawful proposal; or to make a concession shall not constitute, or be direct or indirect evidence of, a breach of this obligation. (Added 1997, No. 92 (Adj. Sess.), § 9.)