Born in Wilmington, Vermont, in 1837, Locke read law to enter the bar in 1859.

Locke served as Paymaster's Clerk in the United States Navy from 1861 to 1865, during the American Civil War.

Locke served as a Judge of the Monroe County Court from 1868 to 1870, and as a member of the Florida Senate from 1870 to 1872.

[1] President Ulysses S. Grant nominated Locke to the United States District Court for the Southern District of Florida on January 15, 1872, to the seat vacated by Judge John McKinney.

He was President Grant's longest-serving judicial appointee, and the longest to have served as a federal judge in Florida.