N.J. Stat. § 43:16A-3.7
Any officer eligible to become a member pursuant to the amendatory provisions of this act who is enrolled in the Public Employees' Retirement System (P.L. 1954, c.84, C. 43:15A-1 et seq.) or any county pension fund established under Title 43 of the Revised Statutes shall be permitted to transfer membership from the aforesaid system or fund to the Police and Firemen's Retirement System of New Jersey in accordance with the provisions of P.L. 1973, c.156 (C. 43:16A-62 et seq.) and upon a lump sum payment into the Police and Firemen's Retirement System annuity savings fund of the amount of the difference between the contribution which was paid as a member of the Public Employees' Retirement System or county pension fund and the contribution that would have been required if he had been a member of the Police and Firemen's Retirement System since the date of last enrolling in the Public Employees' Retirement System or a county pension fund. In addition, the employee shall be liable for any payment to the retirement system that the employer would have been required to make on behalf of the member for the purchase of such credit; this payment may be made in regular monthly installments or in a lump sum, as the employee may elect, and pursuant to rules and regulations as may be promulgated by the board of trustees.
Whenever in P.L. 1973, c.156 a period of time is set which is to be calculated from the effective date of said act, such time shall be calculated from the effective date of this amendatory and supplementary act for the purposes hereof.
N.J.S. § 43:16A-3.7