In mediæval Engand, the sheriffs originally possessed sovereign authority to release or hold suspected criminals. Some sheriffs would exploit the bail for their own gain. The Statute of Westminster (1275) limited the discretion of sheriffs with respect to the bail. Although sheriffs still had the authority to fix the amount of bail required, the statute stipulates which crimes are bailable and which are not.

In the early 17th century, King Charles I ordered noblemen to issue him loans. Those who refused were imprisoned. Five of the prisoners filed a habeas corpus petition arguing that they should not be held indefinitely without trial or bail. In the Petition of Right (1628) the Parliament argued that the Monarch had flouted the Magna Carta by imprisoning people without just cause.

The Habeas Corpus Act 1679 states, "A Magistrate shall discharge prisoners from their Imprisonment taking their Recognizance, with one or more Surety or Sureties, in any Sum according to the Magistrate's discretion, unless it shall appear that the Party is committed for such Matter or offenses for which by law the Prisoner is not bailable."

The English Bill of Rights (1689) states that "excessive bail hath been required of persons committed in criminal cases, to elude the benefit of the laws made for the liberty of the subjects. Excessive bail ought not to be required." This was a precursor of the Eighth Amendment to the US Constitution.

Bail law in the United States

In colonial America, bail law was based on English law. Some of the colonies simply guaranteed their subjects the protections of British law. In 1776, after the Declaration of Independence, those which had not already done so enacted their own versions of bail law.

Section 9 of Virginia's Constitution states "excessive bail ought not to be required..." In 1785, the following was added, "Those shall be let to bail who are apprehended for any crime not punishable in life or limb...But if a crime be punishable by life or limb, or if it be manslaughter and there be good cause to believe the party guilty thereof, he shall not be admitted to bail."

Section 29 of the Pennsylvania Constitution of 1776 states that "Excessive bail shall not be exacted for bailable offences: And all fines shall be moderate."

The Eighth Amendment in the US Federal Bill of Rights is derived from the Virginia Constitution, "Excessive bail shall not be required...", in regard to which Samuel Livermore commented, "The clause seems to have no meaning to it, I do not think it necessary. What is meant by the term excessive bail...?" The Supreme Court has never decided whether the constitutional prohibition on excessive bail applies to the States through the Fourteenth Amendment.

The Sixth Amendment to the Constitution, like the English Habeas Corpus Act of 1679, requires that a suspect must "be informed of the nature and cause of the accusation" and thus enabling a suspect to demand bail if accused of a bailable offense.

The Judiciary Act of 1789

In 1789, the same year that the United States Bill of Rights was introduced, Congress passed the Judiciary Act of 1789. This specified which types of crimes were bailable and set bounds on a judge's discretion in setting bail. The Act states that all non-capital crimes are bailable and that in capital cases the decision to detain a suspect, prior to trial, was to be left to the judge.

The Judiciary Act states, "Upon all arrests in criminal cases, bail shall be admitted, except where punishment may be by death, in which cases it shall not be admitted but by the supreme or a circuit court, or by a justice of the supreme court, or a judge of a district court, who shall exercise their discretion therein."

The Bail Reform Act of 1966

In 1966, Congress enacted the Bail Reform Act of 1966 which states that a non-capital defendant is to be released, pending trial, on his personal recognizance or on personal bond, unless the judicial officer determines that such incentives will not adequately assure his appearance at trial. In that case, the judge must select an alternative from a list of conditions, such as restrictions on travel. Individuals charged with a capital crime, or who have been convicted and are awaiting sentencing or appeal, are to be released unless the judicial officer has reason to believe that no conditions will reasonably assure that the person will not flee or pose a danger. In non-capital cases, the Act does not permit a judge to consider a suspect's danger to the community, only in capital cases or after conviction is the judge authorized to do so.

The 1966 Act was particularly criticized within the District of Columbia, where all crimes formerly fell under Federal bail law. In a number of instances, persons accused of violent crimes committed additional crimes when released on their personal recognizance. These individuals were often released yet again.

The Judicial Council committee recommended that, even in non-capital cases, a person's dangerousness should be considered in determining conditions for release. The District of Columbia Court Reform and Criminal Procedure Act of 1970 allowed judges to consider dangerousness and risk of flight when setting bail in noncapital cases.

Current U.S. bail law

In 1984 Congress replaced the Bail Reform Act of 1966 with new bail law, codified at United States Code, Title 18, Sections 3141-3150. The main innovation of the new law is that it allows pre-trial detention of individuals based upon their danger to the community; under prior law and traditional bail statutes in the U.S., pre-trial detention was to be based solely upon the risk of flight.

18 USC 3142(f) provides that only persons who fit into certain categories are subject to detention without bail: persons charged with a crime of violence, an offense for which the maximum sentence is life imprisonment or death, certain drug offenses for which the maximum offense is greater than 10 years, repeat felony offenders, or if the defendant poses a serious risk of flight, obstruction of justice, or witness tampering. There is a special hearing held to determine whether the defendant fits within these categories; anyone not within them must be admitted to bail.

State bail laws

Bail laws vary somewhat from state to state, as is typical of U.S. jurisprudence. Generally, a person charged with a non-capital crime is presumptively entitled to be granted bail. Recently, some states have enacted statutes modeled on federal law which permit pretrial detention of persons charged with serious violent offenses, if it can be demonstrated that the defendant is a flight risk or a danger to the community. Some states have very strict guidelines for judges to follow, with a published bail schedule. Some states go so far as to require certain forfeitures, bail, and fines for certain crimes.