Membership in a contributory retirement system is mandatory for nearly all Massachusetts public employees who are regularly employed on a full-time basis. A complete guide to the Massachusetts public retirement law can be viewed here.Click here for a complete guide to the Massachusetts Public Pension law. Massachusetts law requires all public retirees to file an affidavit verifying their eligibility to receive a retirement allowance. Section 10: Resignation, failure of reappointment, removal or discharge. If you are actively employed or on a leave of absence you may file your application to retire up to 120 days before you plan to retire. Please complete Section A, the top portion of the attached Retirement Withdrawal Notice. Print all information, except your signature. Massachusetts General Laws, Chapter 32. The system provides retirement, disability, survivor, and death benefits to members and their beneficiaries.