Conn. Gen. Stat. § 5-178: Probation officers.

Any municipal employee who has been taken into state service under the provisions of section N231 of the November, 1955, supplement to the general statutes shall be credited with his entire period of service as a municipal employee for retirement purposes; provided he has made retirement contributions for each year of his municipal service, based upon his salary for such year, equal to those he would have made had he been a member during such period.