CBP officials had legitimate reasons for placing lookouts on American journalists, attorneys, and others suspected of organizing or being associated with the migrant caravan. However, many CBP officials were unaware of CBP’s policy related to placing lookouts and, therefore, may have inadvertently placed lookouts on these Americans, which did not fully comport with the policy. Additionally, CBP officials did not remove lookouts promptly once they were no longer necessary and, as a result, subjected some of these U.S. citizens to repeated and unnecessary secondary inspections. During the same time period, a CBP official requested that Mexico deny entry to caravan associates, including 14 Americans. Unlike CBP’s legitimate reasons for placing lookouts on these U.S. citizens, CBP had no genuine basis for requesting Mexico to deny entry to these individuals. On several other occasions throughout Operation Secure Line, other CBP officials also improperly shared the names and sensitive information of U.S. citizens with Mexico. We made six recommendations that will improve CBP’s controls on placing and removing lookouts and sharing Americans’ sensitive information with foreign countries. CBP concurred with all six recommendations.