13 U.S.C. § 6 — Information from other Federal departments and agencies; acquisition of reports from other governmental and private sources

(a) The Secretary can call on any other federal department, agency, or establishment — including agencies of the District of Columbia government — whenever the Secretary considers it advisable, to get information relevant to the work this title covers. (b) The Secretary can also acquire copies of records, reports, and other material — by purchase or another method — from states, counties, cities, or other units of government (or their instrumentalities), or from private people and agencies. This is allowed whenever such material is needed to run the censuses and surveys covered by this title efficiently and economically. (c) As much as possible, while still keeping the kind, timeliness, quality, and scope of statistics that are actually needed, the Secretary must use information already available from the sources described in (a) or (b), instead of going out and asking people the questions directly.