In March 1849, Congress enacted a bill establishing a census board whose membership consisted of the secretary of state, the attorney general, and the postmaster general. The law authorized this board to prepare and cause to be printed such forms and schedules as may be necessary for the full enumeration of the inhabitants of the United States; it also authorized the board to prepare forms and schedules for collecting information on mines, agriculture, commerce, manufactures, education, and other topics, as well as "exhibit a full view of the pursuits, industry, education, and resources of the country."

The seventh census was governed by the provisions of an act of May 23, 1850 that directed that six schedules be used to collect the information requested by the Congress. The act directed enumerators to return their results to the secretary of the interior by November 1, 1850.

The number of population inquiries grew in the 1850 census. Every free person's name was to be listed, not just the head of the household. The marshals also collected additional "social statistics," including information on taxes, schools, crime, wages, value of the estate, etc. and data on mortality.

Each marshal was also responsible for subdividing his district into "known civil divisions," such as counties, townships, or wards, and ensuring that his assistants' returns were completed properly.