805 ILCS 5/2.25
Unless the power to make, alter, amend or repeal the by-laws is reserved to the shareholders by the articles of incorporation, the by-laws of the corporation may be made, altered, amended or repealed by the shareholders or the board of directors, but no by-law adopted by the shareholders may be altered, amended or repealed by the board of directors if the by-laws so provide. The by-laws may contain any provisions for the regulation and management of the affairs of the corporation not inconsistent with law or the articles of incorporation.
(from Ch. 32, par. 2.25)
(Source: P.A. 83-1025.)