Muslim public officer is obliged and responsible as a Muslim to serve his country and society in every possible way provided he does not take part or support injustice, discrimination and any unlawful act. Things which are legal in non Muslim countries but forbidden in Islam like abortion, alcohol, etc, must be avoided by the Muslim officer. You can leave it for other officers who do not have religious obligations against it.
Haraam is Haraam whether you are an officer or not. We as Muslims are responsible to avoid Haraam in every possible way.