CRS report via FAS – Bail: An Overview of Federal Criminal Law, Charles Doyle, Senior Specialist in American Public Law, July 31, 2017.

“This is an overview of the federal law of bail. Bail is the release of an individual following his arrest upon his promise—secured or unsecured; conditioned or unconditioned—to appear at subsequent judicial criminal proceedings. An accused may be denied bail if he is unable to satisfy the conditions set for his release. He may also be denied bail if the committing judge or magistrate concludes that no amount of security or any set of conditions will suffice to ensure public safety or the individual’s later appearance in court. The federal bail statute layers the committing judge’s or magistrate’s bail options after arrest and before trial. He may release the individual upon his promise to return—that is, on personal recognizance or under an unsecured appearance bond. Alternatively, the judge or magistrate may condition the individual’s release on the least restrictive possible combination of individual or statutory conditions. The statute, however, creates a presumption against release when the individual has been charged with a serious drug, firearms, or terrorist offense. In the case of these and other serious offenses, the judge or magistrate may deny release on bail if he decides, after a hearing, that no set of conditions will guarantee public safety or the individual’s return to court. The judge or magistrate may also deny the individual bail in order to transfer him for bail, parole, or supervised release revocation proceedings. Bail is available to a more limited extent after the individual has been convicted and is awaiting a pending appeal. Federal law also authorizes the arrest, bail, or detention of individuals with evidence material to the prosecution of a federal offense. With limited variations, federal bail laws apply to arrested material witnesses. Although not specifically mentioned in the federal bail statute, bail is available in extradition cases under a long-standing Supreme Court precedent which holds that “bail should not ordinarily be granted in cases of foreign extradition” except under “special circumstances.”