Robert Morris Montgomery (May 12, 1849 - June 27, 1920) was a Justice of the Michigan Supreme Court, and a judge of the United States Court of Customs and Patent Appeals.
Montgomery was in the United States Army, Seventh Michigan Cavalry, during the American Civil War, in 1864. He read law to be admitted to the bar in 1870, entering private practice in Pentwater, Michigan, in 1871. He was an assistant assessor of internal revenue for the state of Michigan prior to 1873, and prosecuting attorney for Oceana County from 1873–1879, also maintaining a private practice in Grand Rapids, Michigan from 1873 to 1877, and serving as an assistant U.S. Attorney, for the Western District of Michigan for 1877 to 1881.
His judicial career began with service as a judge of the Seventeenth Judicial Circuit of Michigan, from 1881 to 1888. After a brief return to private practice, Montgomery became an Associate Justice of the Michigan Supreme Court in 1892. He served on that court until 1910, including stints as Chief Justice from 1900 to 1901, and in 1910.
Nominated to the U.S. Court of Customs Appeals by President William Howard Taft, Montgomery was confirmed by the United States Senate on March 30, 1910. He served as presiding judge from 1910 until his death, in 1920.