The office of Attorney General of Montana was established by Article VII, Section 1 of the 1889 Constitution, which required that the attorney general be elected and serve a four-year term. The framers of the state's first constitution believed that, since the state's Legislative Assembly would be in session only briefly every two years, it was necessary for an elected official responsible not to the governor, but to the electorate, to serve as a check upon gubernatorial power. The attorney general was charged with a number of duties, the most important of which included the handling and presentation before the Supreme Court of legal cases in which the state or a county was interested; supervising and assisting county attorneys; giving his written opinion to the Legislative Assembly, state officers and agencies, county attorneys, and boards of county commissioners upon certain legal questions; and participating as a member of several state boards, including the Board of Examiners, the Board of Education, and the Board of Land Commissioners.

Much of the actual legal research work of the Office is done by assistant attorneys general. All communications received by the Office, requests for information or opinions, and litigations are assigned by the first assistant to the other attorneys. Their work is then reviewed by the first assistant and final approval or disapproval is made by the attorney general. While the assistant attorneys general are not permitted to engage in the private practice of law, special assistants are hired, generally on a part-time basis, and they are permitted to continue private practice if that practice does not create a conflict of interest with state employment. In addition, various state agencies hire legal counsels, often from private firms; these counsels are required to keep the attorney general apprised of the work they were doing for the state. While the attorney general cannot prevent the employment of legal counsel by the various state agencies, he can refuse to give those counsels an appointment as a special assistant, in which case the counsel can not make court appearances on behalf of the state.

The attorney general is sometimes called upon to issue an official opinion, an expression of the legal reasons and principles upon which a decision should be based, reflecting the state's stand on law. Much more frequently, the attorney general issues informal opinions for state agencies and certain others, such as county attorneys and county commissioners. Informal opinions or "letter opinions," are based upon citations of statute or earlier formal opinions. While the attorney general is not permitted by statute to give formal opinions to those outside state agencies and certain political subdivisions, he does at times provide a general legal view of a particular situation to individuals or groups making inquiry.