The governing body of each school district and of each employing unit coming under this System and the State Comptroller or other State officer certifying payroll vouchers shall take the steps necessary to comply with the requirements of Section 414(h)(2) of the Internal Revenue Code of 1986, as amended, to permit the pickup of optional contributions on a tax-deferred basis. Beginning July 1, 1998, a school district or other employing unit shall not withhold optional contributions from the salary of any member on an after-tax basis.
40 ILCS 5/16-154