Tax
Federal government can subpoena business records from a previous year that have already been the target of inspection in prior tax years, so long as the second subpoena is not for the purposes of reopening the audit of the previous year's returns.
http://media.ca7.uscourts.gov/cgi-bin/rssExec.pl?Submit=Display&Path=Y2016/D02-01/C:14-3789:J:Sykes:aut:T:fnOp:N:1695969:S:0
Since 2011. An occasional commonplacing of the U.S. Circuit Courts of Appeal.
Neither an authoritative statement of the law nor legal advice. Quick work.