Memorandum on Ending 'Catch and Release' at the Border of the United States and Directing Other Enhancements to Immigration Enforcement, April 6, 2018 [open pdf - 211KB]
From the Purpose: "Human smuggling operations, smuggling of drugs and other contraband, and entry of gang members and other criminals at the border of the United States threaten our national security and public safety. The backlog of immigration-related cases in our administrative system is alarmingly large and has hindered the expeditious adjudication of outstanding cases. Border-security and immigration enforcement personnel shortages have become critical."
Compilation of Presidential Documents: http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=CPD
Daily Comp. Pres. Docs., 2018 DCPD No. 00255