Proceeding pursuant to CPLR article 78 to review respondent’s determination, dated July 7, 1975, which, after a hearing, fined petitioner five days’ pay and reprimanded him for certain violations of the rules and regulations of the Nassau County Police Department. Determination confirmed and proceeding dismissed on the merits, without costs or disbursements. We will not substitute our own judgment for that of the administrative officer, whose ability and knowledge have been recognized by confiding in him the operation and administration of a sensitive governmental function, where it has not been shown that his decision was unfair or capricious (see Matter of De Boer v Looney, 60 Misc 2d 673, affd 34 AD2d 674). Furthermore, we find the penalty imposed to be reasonable in light of all of the circumstances (see Matter of Stolz v Board of Regents of Univ. of State of N. Y, 4 AD2d 361). Gulotta, P. J., Martuscello, Latham, Margett and Shapiro, JJ., concur.