A
Republican, Peterson was first elected to the House in 1974, representing the old District 27B, and was re-elected in 1976. In 1980, he ran for the Senate, defeating incumbent
Democrat Howard Olson. He was re-elected in 1982. He represented the old Senate districts 27 and 29, changing somewhat after the 1982 legislative
redistricting. During his time in the legislature, he served all or portions of
Blue Earth,
Cottonwood,
Faribault,
Freeborn,
Jackson,
Martin,
Nobles,
Waseca and
Watonwan counties in the southern part of the state. Peterson was a member of the Commerce and Economic Development, Education, Health and Welfare, Labor-Management Relations, and Taxes committees in the House. Later, in the Senate, he was a member of the Education, Elections and Ethics, Energy and Housing, Judiciary, Public Utilities and State Regulated Industries, Taxes and Tax Laws committees. While in the Senate, Peterson also served on the Education subcommittees for Education Aids, for Educational Operation and Governance and for Post-Secondary and Higher Education, of the Energy and Housing Subcommittee for Research and Alternative Financing, of the Judiciary subcommittees for Criminal Law and for Judicial Administration, of the Public Utilities and State Regulated Industries Subcommittee for Public Utilities, and of the Taxes and Tax Laws subcommittees for Agricultural Property Tax and for Natural Resources Tax. His special legislative concerns included education, agriculture, and job development. ==Appointment to Minnesota Public Utilities Commission==