Miss. Code Ann. § 61-3-31: Miss. Code Ann. § 61-3-31

After the publication of such authorizing resolution or amendatory resolution, if any, the validation of the bonds authorized thereby may be contested only if:

(a) Such bonds were authorized for an objective or purpose for which the political subdivision is not authorized to expend money, or

(b) The provisions of law which should have been complied with, on or before the date of such publication, were not complied with, and an action, suit or proceeding contesting such validity is commenced within twenty days after such publication of the resolution authorizing the bonds, or, as to changes made by an amendatory resolution, within twenty days after such publication of such amendatory resolution, or

(c) Such bonds were authorized in violation of the provisions of the constitution or laws of Mississippi.