Look into becoming his POA or Guardian first (if he is disabled), then provide proof in original documents to NYCERS by mail or at 340 Jay Street in downtown Brooklyn. If u visit NYCERS.org there is a Power of Attorney form (F204) there, or you can call them and ask to have one faxed or e-mailed to you.
I don't know the answer you would have to call NYCERS
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