If you zoom in, you can the original purpose of the building, carved over the door: this was built in 1911 as the First Precinct house of the NYPD. The first precinct includes Wall Street and City Hall, so perhaps the over-the-top architecture is to be expected. The building is too small and poorly laid out for modern police use, and now houses the NYPD museum.
It is the most elaborate of our collection of elaborate police stations.
