(a) The Police Department and the members thereof shall, under the overall direction of the Mayor and the immediate direction of the Chief of Police, protect persons and property and preserve law and order within the city, and for such purposes all police officers shall have the powers and authority conferred on municipal police officers by state law.
(b) Members of the Police Department shall be vigilant in the enforcement of the laws of the state as they may be applicable within this city and the enforcement of the provisions of this Code and other ordinances of the city. They shall cooperate with other city officers and employees.