§ 552. Optional twenty year retirement plan for certain members whose employer elects to provide same. a. Any member of the retirement system may elect to become a member pursuant to the provisions of this section within one year after he or she becomes a member, if his or her employer has elected to make the benefits provided herein available to members, or within one year after his or her employer elects to make the benefits provided herein available to its members.

b. Elections made pursuant to this section shall be in writing and shall be duly acknowledged and filed with the comptroller. Any member who files such an election pursuant to this section may withdraw it after it has been filed for at least a year. Such withdrawal shall be by written notice duly acknowledged and filed with the comptroller.

c. A member participating on the basis of this section at the time of retirement, shall be entitled to retire after the completion of twenty years of total creditable service or upon the attainment of age sixty-two, by filing an application therefor in a manner similar to that provided in this chapter.

1. Upon completion of twenty years of such service and upon retirement, each such member shall receive a pension sufficient to provide him or her with a retirement allowance equal to one-fortieth of his or her final average salary for each year of total creditable service for which he or she is otherwise entitled but not exceeding in the aggregate one-half of his or her final average salary.

2. Upon attainment of age sixty-two and upon retirement without completion of twenty years of such service, each such member shall receive a pension sufficient to provide him or her with a retirement allowance equal to one-fortieth of his or her final average salary for each year of creditable service. Every such member shall also be entitled to an additional pension equal to the pension for any other creditable service rendered as otherwise provided for in this chapter. This latter pension shall not increase the total allowance to more than one-half of his or her final average salary.

d. The increased pensions to such members, as provided by this section, shall be paid from additional contributions made by the participating employer on account of such members. The actuary of the retirement system shall compute the additional contribution required for each member who elects to receive the special benefits provided under this section. Such additional contributions shall be computed on the basis of contributions during the prospective service of such member which will cover the liability of the retirement system for such extra pensions. Upon approval of the comptroller, such additional contributions shall be certified by him or her to the chief fiscal officer of the participating employer. The amount thereof shall be included in the annual appropriation of the participating employer. Such amount shall be paid on the warrant of the chief fiscal officer of the participating employer to the pension accumulation fund of the retirement system.

e. In computing the twenty years of completed service of a member, full credit shall be given for military service as defined in subdivisions twenty-nine-a and thirty of section three hundred two of this chapter.

f. Every member participating on the basis of this section shall be separated from the service on the last day of the calendar month next succeeding the calendar month in which he or she attains age sixty-two, provided, however, that such a member who attained the age of sixty-two before his or her employer elected to make the benefits provided herein available to him or her, or who attains the age of sixty-two within one month after his or her employer makes such benefits available, to be eligible for a pension computed in accordance with the provisions of this section, shall be separated from the service within three months after his or her employer makes such benefits available.

g. The provisions of this section shall be controlling notwithstanding any provision in this article to the contrary.

h. The benefits of this section shall be available only to those members whose employer elects to provide such benefits by adopting a resolution to such effect and filing a certified copy thereof with the comptroller.

i. The benefits hereinabove provided shall be payable to a member, unless at the date of retirement, such member would otherwise be entitled to a greater benefit under other provisions of this chapter had he or she withdrawn from this section, in which event such greater benefits shall be payable.

j. 1. As used in this section "creditable service" shall include, any and all services performed as a sheriff, undersheriff or deputy sheriff, provided, however, that criminal law enforcement service shall only be creditable when it aggregates fifty per centum or more of his or her service as a deputy sheriff.

2. Notwithstanding the provisions of paragraph one of this subdivision, a participating employer may elect on a form filed with the comptroller for that purpose to provide that creditable service shall also include any and all service performed by a deputy sheriff who is a police officer pursuant to subdivision thirty-four of section 1.20 of the criminal procedure law as certified by the municipal police council or as certified by the police department of the city of New York upon satisfactory completion of the basic training program and graduation from the New York city police academy.

3. Credit for service as a member or officer of the state police or as a paid firefighter, police officer or officer of any organized fire department or police force or department of any county, city, village, town, fire district or police district, or as a criminal investigator in the office of a district attorney, provided that service as such investigator shall have been rendered prior to January first, nineteen hundred sixty and that credit therefor shall not exceed five years, shall also be deemed to be creditable service and shall be included in computing years of total service for retirement pursuant to this section, provided such service was performed by the member while contributing to the retirement system pursuant to the provisions of this article or article eight of this chapter.

k. As used in this section, "creditable service" shall also include any and all services performed as an employee of the Columbia county sheriff's department, provided that such employment was performed on or before December thirty-first, nineteen hundred ninety-five and provided that on that date the employee was performing criminal law enforcement duties in the Columbia county sheriff's department.