(a) Chapter 710 of the Laws of 1989 amended sections 90 and 390 of the Retirement and Social Security Law. As so amended, these sections provide that disability retirement shall become effective on the day before death where:

Chapter 710 is retroactive so as to apply to otherwise eligible members who died on or after August 7, 1987. However, under prior law, ordinary death benefits, rather than post-death retirement benefits under a retirement option, would have been payable on account of the death of individuals covered by Chapter 710.

(b) Under Chapter 710, optional benefits are not payable on account of the death of individuals who died between August 7, 1987 and the July 24, 1989 effective date of Chapter 710, where the beneficiary(ies) are not the same as the beneficiary(ies) of ordinary death benefits which were payable under prior law. The other instances where Chapter 710 will not be applied retroactively are where retroactive application would reduce the amounts payable to the same beneficiary on account of the death of a member. Retroactive application of Chapter 710 under these circumstances would be violative of the State Constitution's prohibition against diminution of rights and benefits in a public retirement system. Accordingly, this part is promulgated to provide guidelines for the administration of Chapter 710, with emphasis on retroactive application.