H.R. 5163 would focus on addressing the increased influx of unaccompanied alien children (UACs) on the Southwest border. First and foremost, it removes the distinction between UACs from contiguous and noncontiguous countries, then requires those who are screened and do not qualify are returned within 72 hours. Various improvements are made to the system for processing UACs, including a new requirement that they are to remain in Border Patrol custody until voluntary departure, removal, or granting of legal status. Similarly, those applying for admission remain in mandatory detention until asylum is granted or they are ordered removed. In addition, the bars for reentry are increased for those who are removed as well as those who entered illegally, and SCAAP funding is denied to sanctuary cities. Finally, the bill makes a significant change to the definition of a refugee or asylee, replacing the "well-founded fear" requirement with a more specific requirement that an individual's "life or freedom would be threatened" in his or her home country.