On May 1, 1877, during the building's construction, three workers were killed when a concrete slab collapsed, prompting an investigation by the city and a public rebuttal of accusations of misconduct from Mullett.Regarding the building's lack of popularity, The New York Times wrote in 1912: The Mullett Post Office has always been an architectural eyesore, and has, from the first, been unsatisfactory to the Postal Service and the Federal Courts beneath its roof. It was known as "Mullett's Monstrosity".