No agency shall expend or contract to expend any money or incur any liability in excess of the amounts appropriated for that purpose: PROVIDED, That nothing in this section shall prevent the making of contracts or the spending of money for capital improvements, nor the making of contracts of lease or for service for a period exceeding the fiscal period in which such contract is made, when such contract is permitted by law. Any contract made in violation of this section shall be null and void.
RCW 43.88.130