The Secretary may conduct special censuses for the government of any State, or of any county, city, or other political subdivision within a State, for the government of the District of Columbia, and for the government of any possession or area (including political subdivisions thereof) referred to in section 191(a) of this title, on subjects covered by the censuses provided for in this title, upon payment to the Secretary of the actual or estimated cost of each such special census. The results of each such special census shall be designated “Official Census Statistics”. These statistics may be used in the manner provided by applicable law.
13 U.S. Code § 196 - Special censuses
Statutory Notes and Related Subsidiaries
Special Census When Major Population Changes Occur Due to Large Numbers of Legal Immigrants Within Six Months of Regular Decennial Census Date
“Notwithstanding any other provision of law, when the President determines that a State, county, or local unit of general purpose government is significantly affected by a major population change due to a large number of legal immigrants within six months of a regular decennial census date, he may order a special census, pursuant to section 196 of title XIII of the United States Code [this section], or other method of obtaining a revised estimate of the population, of such jurisdiction or subsections of that jurisdiction in which the immigrants are concentrated. If the President decides to conduct a special census, it may be conducted solely at Federal expense.”