Section 588.6 - Suit for collection of tax(a) It shall be the duty of the Board of Public Education of the school district imposing a tax under this act, or the treasurer, if designated by the board, to sue for the recovery of all taxes not paid when due.(b) Any suit brought to recover the tax imposed under this act shall be begun within six (6) years after such tax is due or within six (6) years after a declaration or return has been filed, whichever date is later: Provided, That this limitation shall not prevent the institution of a suit for the collection of any tax due or determined to be due in the following cases: (1) Where no declaration or return was filed by any person although a declaration or return was required to be filed by him under the provisions of this act.(2) Where an examination of the declaration or return filed by any person, or of other evidence relating to such declaration or return, in the possession of the treasurer, reveals a fraudulent evasion of taxes, including, but not limited to, substantial understatement of taxes deducted and of actual or estimated net profits or earnings.(3) Where any person has deducted taxes under the provisions of this act and has failed to pay the amounts so deducted to the treasurer.1961, Aug. 24, P.L. 1135, No. 508, § 6.