In 1967 the legislature created the Department of Public Service (see Laws 1967, chap. 864), consisting of two branches: the Public Service Commission and the Administrative Division. This effectively renamed and transferred all the duties of the Railroad and Warehouse Commission to the newly created Public Service Commission. In 1975 the Public Service Commission began regulating gas and electric companies (see Laws 1974, chap. 429). This law also changed the composition from three Commissioners serving for six years to five Commissioners serving for terms of five years. The director of the administrative division was appointed for a four-year term. As executive and administrative head of the department, he was charged with expediting and supervising the enforcement of all orders and directives of the commission.
The Public Service Department was an investigative and enforcement agency with jurisdiction over rates and services of public storage warehouses, telephone companies, and, since 1975, public utilities. It was involved with grain inspection and weighing and livestock regulation until 1974, when those functions were transferred to the Department of Agriculture (see Laws 1974, chap. 347 and chap. 548).
A 1979 report by the Legislative Auditor noted a strained relationship between the Director of the Administrative Division of the Department of Public Service and the Commissioners of the Public Service Commission, and recommended structural changes. The 1980 legislature responded by separating the two and establishing them as independent state agencies: the Department of Public Service and the Public Utilities Commission (see Laws 1980, chap. 614, sec. 103). The Public Service Department and the Public Utilities Commission, although separate agencies, continued to work cooperatively, conducting joint projects, making recommendations to each other, and sharing services and costs when beneficial to both.
Until 1980, the Public Service Department also had jurisdiction over rates and services of railroad companies and for-hire carriers (e.g. buses, trucks). The Transportation Regulation Board, a three-member independent quasi-judicial board, was then created to take over those functions (Laws 1980, chap. 534). As a public advocate in utility rate matters, the department investigates issues that affect rates, revenues, or quality of service.
In 1987, the Legislature restructured the Energy and Economic Development Department. The energy-related functions of that department were given over to the Public Services Department. At the same time, a new department was created: the Trade and Economic Development Department. This new department assumed the remaining former duties of the Energy and Economic Development Department.
The Public Service Department was abolished in 2001 (see Laws 2001, 1st Sp. Sess., chap. 4, art. 6, sec. 1), and "all of the powers, rights, responsibilities, and duties that remain in the department of public service after reorganization order No. 181 are transferred to the department of commerce... The department of public service is abolished."