CBP's ACAS Program Did Not Always Prevent Air Carriers from Transporting High-Risk Cargo into the United States

U.S. Customs and Border Protection (CBP) identified and targeted high-risk cargo shipments, CBP did not always prevent air carriers from transporting high-risk air cargo from foreign airports into the United States.  This occurred because neither CBP nor TSA developed adequate policies and procedures to ensure air carriers resolved referrals timely or appropriately.  We made four recommendations to CBP and TSA to mitigate a number of vulnerabilities in the Air Cargo Advance Screening Program.  CBP and TSA concurred with all four recommendations.