(a) In this section:
(1) “First responder” means an individual listed under § 615.003, Government Code.
(2) “Residence homestead” has the meaning assigned by § 11.13.
(3) “Surviving spouse” means the individual who was married to a first responder at the time of the first responder’s death.
(b) The surviving spouse of a first responder who is killed or fatally injured in the line of duty is entitled to an exemption from taxation of the total appraised value of the surviving spouse’s residence homestead if the surviving spouse:
(1) is an eligible survivor for purposes of Chapter 615, Government Code, as determined by the Employees Retirement System of Texas under that chapter; and
(2) has not remarried since the death of the first responder.

(c) The exemption provided by this section applies regardless of the date of the first responder’s death if the surviving spouse otherwise meets the qualifications of this section.
(d) A surviving spouse who receives an exemption under Subsection (b) for a residence homestead is entitled to receive an exemption from taxation of a property that the surviving spouse subsequently qualifies as the surviving spouse’s residence homestead in an amount equal to the dollar amount of the exemption from taxation of the first property for which the surviving spouse received the exemption under Subsection (b) in the last year in which the surviving spouse received that exemption if the surviving spouse has not remarried since the death of the first responder. The surviving spouse is entitled to receive from the chief appraiser of the appraisal district in which the first property for which the surviving spouse claimed the exemption was located a written certificate providing the information necessary to determine the amount of the exemption to which the surviving spouse is entitled on the subsequently qualified homestead.