Any permanent constable or police officer who is either elected under the provisions of N.H. Rev. Stat. § 41:47 or appointed for full-time duty under the provisions of N.H. Rev. Stat. § 105:1, and who is in compliance with the requirements of N.H. Rev. Stat. § 106-L:6, shall continue to hold such office during good behavior, unless sooner removed for cause by the selectmen, after notice and hearing, or unless the town has rescinded its action as provided in N.H. Rev. Stat. § 41:47. Any such elected permanent constable or police officer shall be deemed to be a permanent policeman, and entitled to benefits under the provisions of N.H. Rev. Stat. Chapter 103 if otherwise qualified.