Frederick Stone (February 7, 1820 – October 17, 1899) was a U.S. Congressman from the fifth district of Maryland, serving two terms from 1867 to 1871.
Stone was born in Charles County, Maryland, and graduated from St. John’s College of Annapolis, Maryland in 1839. He studied law, and was admitted to the bar in 1841, beginning practice in Port Tobacco, Maryland. He was appointed by the legislature in 1852 as one of the commissioners to revise the rules of pleading and practice in the State courts.
Stone was the grandson of Michael J. Stone, the younger brother of Thomas Stone, a signer of the Declaration of Independence. During the Abraham Lincoln assassination trial in May & June 1865, Frederick Stone and Thomas Ewing, Jr. appeared as defense counsels for Dr. Samuel Mudd and David Herold. Their defense is generally credited with helping Dr. Mudd avoid the death penalty.
Stone was a member of the Maryland House of Delegates in 1864 and 1865, and was elected as a Democrat to the Fortieth and Forty-first Congresses (serving March 4, 1867 – March 3, 1871). He was a member of the Constitutional convention of 1867 for Charles County. Stone was an unsuccessful candidate for reelection in 1870, and became an associate judge of the Maryland Court of Appeals, serving from 1881 to 1890. He died at Idaho, his country home near La Plata, Maryland in 1899, and is interred in Mount Rest Cemetery of La Plata. He married (1) Maria Louisa Stonestreet on June 10, 1852. Maria died in November 1867, and he married her sister, (2) Jennie Stonestreet Ferguson, on June 15, 1870.