Sec. 23. (a) Except as provided in subsection (b), any sums in a joint account may be paid, on request, to any party without regard to whether any other party is incapacitated or deceased at the time the payment is demanded.
(b) Payment may not be made to the personal representative or heirs of a deceased party unless:
(1) proofs of death are presented to the financial institution showing that the decedent was the last surviving party; or
(2) there is no right of survivorship under section 18 of this chapter.