William M. "Boss" Tweed – the corrupt leader of Tammany Hall, a political machine that controlled the New York state and city governments when the courthouse was built – oversaw the building's erection.

The media criticized the project as wasteful and gaudy during the courthouse's construction, and for a century after its completion, there were frequent proposals to demolish the building.

[23] While his obituary in Harper's Weekly praised him profusely,[24] an anonymous writer for the American Architect and Building News said his involvement in the Tweed Courthouse negated the merits of anything else he had designed.

[27] Leopold Eidlitz, who was hired to finish the courthouse in 1876,[28] added the building's south wing and domed rotunda in a similar design to the New York State Capitol.

The New York City Landmarks Preservation Commission (LPC) said Eidlitz's style departs from Kellum's classicism with "an American version of organic architecture expressed through medieval forms".

[8] The original design was inspired by that of the United States Capitol in Washington, D.C.,[8] which was being used for other sub-national government buildings at the time of the Tweed Courthouse's construction.

[24] The most prominent element from the Capitol used in the Tweed Courthouse was a large entry stairway that approached a triangular portico, supported by massive columns in the Corinthian order.

[41] On each side of the northern elevation, there is a flanking bay within the building's main section, as well as a wing that projects northward slightly.

Each of the windows on the northern elevation contains their original pilasters, centered colonnettes, and paneled blind railings, which are set within a marble surround.

[20] An entablature in the Corinthian style surrounds the top of the Tweed Courthouse's northern, western, and eastern elevations and remains mostly intact.

[8] Kellum had designed a portico for the southern wing, similar to that on the northern entrance, but it was left out of Eidlitz's revised plan due to budgetary constraints.

[39] Kellum used classical cast iron and plaster elements such as palmettes, triangular pediments, and geometric banding; he also included large rectangular openings in the rotunda wall on the ground and second floors.

The windows in these rooms contain foliate decoration at the bottom and cartouches at the top, while the fireplaces consist of flat mantelpieces above colonnettes and pilasters.

[30] Tweed, considered one of the most corrupt politicians in United States history, was assisted by a ring of political allies,[59][52] who as a whole embezzled up to $300 million (about $8 billion in 2023[58]).

[60] The author Albert Paine wrote that the collective's "methods were curiously simple and primitive", in that city controller Richard B. Connolly "had charge of the books, and declined to show them".

[66] Ely claimed that "grossly extravagant and improper expenditures have been made [...] in reference to the purchase of iron, marble and brick, and in the payment of various persons for services.

[75] The New York Times published several articles in July 1871, bringing attention to the exorbitant expenditures for materials in the courthouse, which had previously not been disclosed to the public.

[67] The New York Times criticized the new wing's design, calling it "cheap and tawdry in comparison with the elaborate finishing and classic exterior of the present structure".

[93] The following year, the guidebook Miller's New York As It Is described the courthouse in an unbiased perspective:[93] "The court-rooms are large, airy, unobstructed by columns, made with reference to the principles of acoustics, and finished in an agreeable and pleasing manner.

"[94] The corruption associated with the Tweed Courthouse was so potent that, when space for municipal functions became scarce in the late 19th century, mayoral administrations were reluctant to destroy the building, even as they also proposed demolition for the much-admired City Hall.

[96] In 1938, mayor Fiorello H. La Guardia studied the feasibility of destroying the Tweed Courthouse after a suggestion from New York City parks commissioner Robert Moses.

[21] By 1908, Montgomery Schuyler had written that Eidlitz's original rotunda colors had "been shorn of much of it pristine force, which was much promoted by the tri-colored brickwork" following the addition of gray paint.

[21] Mayor Abraham Beame proposed demolishing Tweed Courthouse in March 1974 in conjunction with a restoration of the nearby Manhattan Municipal Building.

[106] These plans elicited criticism from the public, and Beame created a special task force that April to investigate the feasibility of preserving the courthouse.

[21] The conservancy also repainted the interior, though the dilapidated exterior remained untouched, sporting a yellow paint job with black-and-orange stains on the marble.

[49] The city government hired architectural firm John G. Waite Associates in 1989 to prepare a feasibility study for the courthouse, which was completed the next year.

[51][116] After workers discovered old skeletal remains under the courthouse, work on the elevators was temporarily halted while city officials investigated whether the bones were historically significant.

[117] Following the September 11 attacks, which occurred near the courthouse toward the completion of the restoration, the portion of City Hall Park around the building was closed due to security concerns.

[15] Mayor Rudy Giuliani had wanted to relocate the Museum of the City of New York from East Harlem to the newly renovated Tweed Courthouse, a move for which his administration was criticized.

[119][120] Local newspaper Newsday wrote that the museum had "enjoyed favor in [...] Giuliani's administration" and that politicians who represented East Harlem, such as councilman Phil Reed, had opposed the move.