§ 509. Accidental death benefits. a. The eligible beneficiary of a member in service, or a vested member that dies as a result of a qualifying World Trade Center condition as defined in section two of this chapter, shall be entitled to an accidental death benefit in the form of a pension equal to fifty percent of such member's final average salary if, upon application filed within five years after the death of the member, the head of the retirement system determines that such member:

1. Died before the effective date of retirement, as the natural and proximate result of an accident sustained in the performance of duty in the service upon which membership was based, and

2. Did not cause such accident by his or her own willful negligence.

Notwithstanding the provisions of section two hundred forty-two, two hundred forty-three or two hundred forty-four of the military law or the provisions of any other law to the contrary and solely for the purpose of determining eligibility for an accidental death benefit, a member shall be considered to have died as the natural and proximate result of an accident sustained in the performance of duty provided such member was on the payroll in the service upon which membership is based at the time he or she was ordered to active duty pursuant to Title 10 of the United States Code, with the armed forces of the United States or to service in the uniformed services pursuant to Chapter 43 of Title 38 of the United States Code and died while on such active duty or service in the uniformed services on or after June fourteenth, two thousand five.

b. If an eligible beneficiary receiving the accidental death benefit hereunder becomes ineligible to continue to receive such benefit, the benefit shall be continued for all other members of the eligible class of beneficiaries and, if none, to each successive class, if any, during their eligibility therefor.

c. If the aggregate benefits under the provisions of this section have not exceeded the amount of the ordinary lump sum death benefit because of the absence of eligible beneficiaries or because those beneficiaries formerly eligible are no longer eligible for payments pursuant to section five hundred one, then the difference between the amounts, if any, paid under this section and the amount of the ordinary lump sum death benefit shall be paid to:

1. The last eligible beneficiary or beneficiaries, if surviving, who were receiving pension payments hereunder or, if none

2. The distributees of the member, if there were no eligible beneficiaries at the member's death, or the persons who would be distributees of the member had he died intestate on the date that the last eligible beneficiary died or became ineligible.