''This traditional right to freedom before conviction permits the unhampered preparation of a defense, and serves to prevent the infliction of punishment prior to conviction. . . . Unless this right to bail before trial is preserved, the presumption of innocence, secured only after centuries of struggle, would lose its meaning.'' ''The bail clause was lifted with slight changes from the English Bill of Rights Act. In England that clause has never been thought to accord a right to bail in all cases, but merely to provide that bail shall not be excessive in those cases where it is proper to grant bail. When this clause was carried over into our Bill of Rights, nothing was said that indicated any different concept.'' These two contrasting views of the ''excessive bail'' provision, uttered by the Court in the same Term, reflect the ambiguity inherent in the phrase and the absence of evidence regarding the intent of those who drafted and who ratified the Eighth Amendment 

Crucial to understanding why the ambiguity exists if not to its resolution is knowledge of the history of the bail controversy in England. The Statute of Westminster the First of 1275 set forth a detailed enumeration of those offenses which were bailable and those which were not, and, though supplemented by later statutes, it served for something like five-and-a-half centuries as the basic authority. Darnel's Case, in which the judges permitted the continued imprisonment of persons merely upon the order of the King, without bail, was one of the moving factors in the enactment of the Petition of Right in 1628;the Petition cited Magna Carta as proscribing detention of persons as permitted in Darnel's Case. The right to bail was again subverted a half-century later by various technical subterfuges by which petitions for habeas corpus could not be presented, and Parliament reacted by enacting the Habeas Corpus Act of 1679, which established procedures for effectuating release from imprisonment and provided penalties for judges who did not comply with the Act. That avenue closed, the judges then set bail so high it could not be met, and Parliament responded by including in the Bill of Rights of 1689 a provision ''[t]hat excessive bail ought not to be required.'' This language, along with essentially the rest of the present Eighth Amendment, was included within the Virginia Declaration of Rights, was picked up in the Virginia recommendations for inclusion in a federal bill of rights by the state ratifying convention, and was introduced verbatim by Madison in the House of Representatives.  

Thus, in England the right to bail generally was conferred by the basic 1275 statute, as supplemented, the procedure for assuring access to the right was conferred by the Habeas Corpus Act of 1679, and protection against abridgement through the fixing of an excessive bail was conferred by the Bill of Right of 1689. Habeas corpus was here protected in Article I, Sec. 9, of the Constitution and the question is, therefore, whether the First Congress knowingly or inadvertently provided only against abridgement of a right which they did not confer or protect in itself or whether the phrase ''ex cessive bail'' was meant to be a shorthand expression of both rights.

Compounding the ambiguity is a distinctive trend in the United States which had its origin in a provision of the Massachusetts Body of Liberties of 1641,guaranteeing bail to every accused person except those charged with a capital crime or contempt in open court. Copied in several state constitutions, this guarantee was contained in the Northwest Ordinance in 1787, along with a guarantee of moderate fines and against cruel and unusual punishments, and was inserted in the Judiciary Act of 1789, enacted contemporaneously with the passage through Congress of the Bill of Rights. It appears, therefore, that Congress was aware in 1789 that certain language conveyed a right to bail and that certain other language merely protected against one means by which a pre-existing right to bail could be abridged.

Long unresolved was the issue of whether ''preventive detention''--the denial of bail to an accused, unconvicted defendant because it is feared or it is found probable that if released he will be a danger to the community--is constitutionally permissible. Not until 1984 did Congress authorize preventive detention in federal criminal proceedings.  

The Court first tested and upheld under the Due Process Clause of the Fourteenth Amendment a state statute providing for preventive detention of juveniles. Then, in United States v. Salerno, the Court upheld application of preventive detention provisions of the Bail Reform Act of 1984 against facial challenge under the Eighth Amendment. The function of bail, the Court explained, is limited neither to preventing flight of the defendant prior to trial nor to safeguarding a court's role in adjudicating guilt or innocence. ''[W]e reject the proposition that the Eighth Amendment categorically prohibits the government from pursuing other admittedly compelling interests through regulation of pretrial release.'' Instead, ''the only arguable substantive limitation of the Bail Clause is that the government's proposed conditions of release or detention not be 'excessive' in light of the perceived evil.'' Detention pending trial of ''arrestees charged with serious felonies who are found after an adversary hearing to pose a threat to the safety of individuals or to the community which no condition of release can dispel'' satisfies this requirement.  

Bail is ''excessive'' in violation of the Eighth Amendment when it is set at a figure higher than an amount reasonably calculated to ensure the asserted governmental interest. If the only asserted interest is to guarantee that the accused will stand trial and submit to sentence if found guilty, then ''bail must be set by a court at a sum designed to ensure that goal, and no more.'' To challenge bail as excessive, one must move for a reduction, and if that motion is denied appeal to the Court of Appeals, and if unsuccessful then to the Supreme Court Justice sitting for that circuit. The Amendment is apparently inapplicable to postconviction release pending appeal but the practice has apparently been to grant such releases.