The city director of law shall prepare all contracts, bonds, and other instruments in writing in which the city is concerned, and shall serve the several directors and officers provided in Title VII [7] of the Revised Code as legal counsel and attorney.

The director of law shall be prosecuting attorney of the mayor's court. When the legislative authority of the city allows assistants to the director of law, he may designate the assistants to act as prosecuting attorneys of the mayor's court. The person designated shall be subject to the approval of the legislative authority.

The city director of law, when required to do so by resolution of the legislative authority of the city, shall prosecute or defend on behalf of the city, all complaints, suits, and controversies in which the city is a party.

When an officer of a city entertains doubts concerning the law in any matter before him in his official capacity, and desires the opinion of the city director of law, he shall clearly state to the director of law, in writing, the question upon which the opinion is desired, and thereupon the director of law shall, within a reasonable time, reply orally or in writing to such inquiry.