In 1887, Barnes relocated to Rhinelander, and became the first municipal judge of Oneida County, served as president of the local school board, and prospered in business.

[3] In 1905, he was appointed to the newly created Wisconsin Railroad Commission by Governor Robert M. La Follette.

He defeated appointed justice Robert McKee Bashford, and went on to re-election to a full term in 1909.

[2] In 1916, however, Barnes resigned to become general counsel of the Northwestern Mutual Life Insurance Company.

Barnes suffered a stroke at his office in Milwaukee on December 28, 1918, and died four days later, after developing pneumonia.