Section 31-B - Participation by the Upper Hudson Library Systema. The Upper Hudson Library System may, by resolution adopted by its board of trustees and approved by the comptroller, elect to participate in the retirement system. Acceptance of its employees for membership in the retirement system shall be optional with the comptroller, who shall determine the amounts of contribution payable by such system and its employees, shall resolve questions of credit for prior service, and shall in all other respects assure that such employees share the same rights, obligations and benefits as other members of the retirement system.b. The officers and employees of such system shall be credited with such periods of prior service as shall be certified by such system for service rendered to it, or the state, or in any other capacity approved by such system and the comptroller. Service for such system after the date on which it commences to participate in the retirement system shall be considered as member service. An officer or employee of such system who, as of the date he or she is so approved for membership in the retirement system, is already a member thereof, shall not have his or her total credit reduced by such approval. Any reserve held on account of any such officer or employee in the pension accumulation fund shall be used as an offset against the deficiency contribution payable thereafter by such system on account of such officer or employee for any prior service credit and any such previous credit.N.Y. Retire. and Soc. Sec. Law § 31-B