Federal law enforcement’s growing reliance on foreign partners as U.S. prosecutors build cases against targets abroad will have to adjust to a new reality after the U.S. Court of Appeals for the Second Circuit curtailed compelled testimony use in cross-border prosecutions.

The same day the decision came down in United States v. Allen, 16-898-cr, acting assistant attorney general Kenneth Blanco, in remarks to the Atlantic Council Inter-American Dialogue, said the Department of Justice’s “biggest investigations are increasingly transnational, often involving multiple foreign jurisdictions.”