Purchasers of such bonds shall not be obligated to inquire into the validity of the indebtedness funded, and bonds issued under sections 19--8 through 19--11 shall be the valid and binding obligations of the school district, notwithstanding the fact that the bonds, together with existing indebtedness, either in whole or in part, exceed any statutory debt limitation in force at the time the bonds are issued.
105 ILCS 5/19-14