(40 ILCS 5/7-136) (from Ch. 108 1/2, par. 7-136)
    Sec. 7-136. Municipalities and participating instrumentalities covered under the Federal Social Security Act and effective dates. Subject to the provisions of the Agreement with the State Agency as provided in Section 7-170, the following described municipalities (including all instrumentalities thereof), and participating instrumentalities shall be considered covered under the Federal Social Security Act and shall be subject to this Article pertaining to covered municipalities and participating instrumentalities beginning upon the effective dates hereinafter specified:
    (a) All municipalities (and instrumentalities thereof) and participating instrumentalities participating on December 31, 1957 shall be covered as of January 1, 1956;
    (b) All municipalities (and instrumentalities thereof) and participating instrumentalities that begin participation after December 31, 1957, shall be considered covered as of the effective date of participation.
(Source: Laws 1963, p. 161.)