(a) A taxpayer who receives disaster assistance during a taxable year from the Georgia Emergency Management Agency or the Federal Emergency Management Agency shall be allowed a credit against the tax imposed by Code Section 48-7-20 in an amount equal to $500.00 or the actual amount of such disaster assistance, whichever is less. The commissioner may require adequate supporting documentation showing that the taxpayer received such assistance.

(b) In no event shall the total amount of the tax credit under this Code section for a taxable year exceed the taxpayer's income tax liability. Any unused tax credit shall be allowed the taxpayer against succeeding years' tax liability. No such credit shall be allowed the taxpayer against prior years' tax liability.

(c) The commissioner shall be authorized to promulgate any rules and regulations necessary to implement and administer the provisions of this Code section.