This bill amends title 18 of the U.S. Code to modify the criteria for pretrial release and detention. It establishes a rebuttable presumption that any defendant who is not a United States citizen or lawful permanent resident poses a danger to the community and a serious risk of flight. Under this presumption, it is assumed that no condition or combination of conditions will reasonably assure the defendant's appearance in court or the safety of any other person and the community. To overcome this, the defendant must provide clear and convincing evidence to rebut the presumption. Significantly, the bill specifies that ties to family or employment in the United States shall not be considered valid grounds for rebutting this presumption, thereby increasing the likelihood of pretrial detention for non-citizens and non-lawful permanent residents.