The Heitz Place Courthouse, probably the last remaining judicial building in the County dating from the days when Nassau was part of Queens, is an integral part of Long Island's history. Now renovated to house the collections of the Hicksville Gregory Museum, its origin was actually in the Hicksville of the 1880's when it was a well-known German-American community. On August 19, 1893, Arnold Heitz donated the present Heitz Place site for a Village Hall. Bids for the carpentry went to Joseph Funfgeld for $1,900 and those for masonry to Sebastian Brown for $300. The main building was completed in 1895.
Between 1895 and 1920 the Village Hall served a variety of governmental and meeting purposes. At first the building, heated by potbellied stoves, had a two-cell jail on the north side. Justices of the Peace, who were also Town Councilmen, held court once a week. Assistants were elected as part-time constables and caretakers of the jail.
By 1915 the existing jail was deemed inadequate and a bid was accepted from the Pauly Jail Company of St. Louis, Missouri to furnish, adjacent to the Hall, for the sum of $828, a brick three-cell jail. One cell has been retained by the Museum..
During World War I the Heitz Place Courthouse served as headquarters for Selective Service for Eastern Nassau County. The justices who presided in Hicksville over the next forty years were a varied and memorable group. Judge Charles Stoll, a big game hunter, succeeded the long-tenured, respected Judge Joseph Steinert in 1919. Judge Stoll met the growing volume of cases with the introduction of a court stenographer, for which he was criticized as "extravagant". During this period the constables lived upstairs, and the judge's chamber was a small room at the rear of the main courtroom.
The Thirties brought cases reflecting the hardships and despairs of the times. A new judge's chamber was added in 1930 on the south side of the building. After the death of Judge Heberer, the long tenure of Judge Joseph Lebkuecher began. During his term the Heitz Place Courthouse acquired the status as Nassau County's Fourth District Court. Judge Lebkuecher held his seat from 1935 to 1957.
With the commencement of World War II, the Courthouse resumed its function as a Draft Board Headquarters. In the post-war years, the building served several new purposes. The parole officers were located there, and the Town's Veterans Agency official, Joseph McCarthy, counseled returning servicemen.
By the late Fifties, the District Court's jurisdiction had changed. Cases were limited to those of non-jury disposition. Judge Francis Donovan presided until 1967 when Nassau County moved its Fourth District Court in Hicksville to new quarters. The Heitz Place Courthouse fell prey to vandals until 1970, when arrangements were made between officials of the Town of Oyster Bay and the Trustees of the Museum for a long term lease of the facility to serve as a Long Island Earth Science Museum.
The United States Department of the Interior recognized the building as a National Historic Place on July 30, 1974.