The granite-faced hexagonal building was designed by Guy Lowell of Boston in classical Roman style and was built between 1913 and 1927, completion having been delayed by World War I.

A broad set of steps sweeps up from Foley Square to a massive Corinthian colonnade covering most of the front of the courthouse, topped by an elaborate 140-foot-long (43 m) triangular pediment of thirteen figures carved in bas relief from granite.

A frieze bears the inscription "The true administration of justice is the firmest pillar of good government", a quotation taken from a letter written by George Washington to Attorney General Edmund Randolph on September 28, 1789.

[10] The error was apparently made by the architect, Guy Lowell, and the mistake was repeated by others, including Charles Warren in his Pulitzer Prize–winning The Supreme Court in United States History (1922).

[6] The stone steps leading up to the colonnaded entrance were flanked by two allegorical statues, Justice and Authority, both designed by the Franco-American sculptor Philip Martiny (1858–1927).

[15] Each depicts a pair of figures from historical cultures important to the history of law: Assyrian and Egyptian, Hebraic and Persian, Greek and Roman, Byzantine and Frankish, English and early colonial, with the final section portraying George Washington and Abraham Lincoln.

[18] The restoration project, which was privately funded by money raised from New York City judges and attorneys,[15][17] was part of a broader renovation campaign in the 1980s and 1990s to protect the courthouse's historic art from water seepage and other damage caused by neglect.