The Department of Homeland Security’s (DHS) own watchdog says that drones deployed at the United States-Mexico border do not achieve their objective of protecting the country.

In a 37-page report issued on December 24, 2014 but published for the first time on Tuesday, DHS’ Office of the Inspector General (OIG) concluded that “after 8 years, [Customs and Border Protection, or CBP] cannot prove that the program is effective because it has not developed performance measures.”

In a statement, the agency had a damning conclusion for the CBP drone program, which anticipates spending an additional $443 million to acquire and operate 14 more drones.