Subject to rules adopted by the board of trustees, the retirement system shall accept an eligible rollover distribution or a direct transfer of funds from another qualified plan in payment of all or a portion of any deposit a member is permitted to make with the system for credit for service. The rules adopted by the board shall condition the acceptance of a rollover or transfer from another plan on the receipt from the other plan of information necessary to enable the retirement system to determine the eligibility of any transferred funds for tax-free rollover treatment or other treatment under federal income tax law.