Bail is the release from custody of a person charged with an offence, on that person's signed undertaking that they will appear in court to answer the charge. This undertaking is a pledge they make when they sign the bail bond entitling them to conditional freedom. A person on bail who does not appear when required to do so, or who breaches one or other of their bail conditions, can be arrested and may be charged with a criminal offence.

The release of an accused on bail is usually invoked for the more serious offences. For offences such as traffic offences or misdemeanours, the police usually serve a charge and summons to appear at court at a later date. This also happens for most Children's Court offences (see: "Types of cases" in Chapter 6.2 Children's Court).

The law in Victoria relating to bail is found in the Bail Act 1977 (Vic) ("Bail Act"). This Act applies not only to offences charged under state law, but also to relevant Commonwealth offences by virtue of sections 68(1), 79 and 80 of the Judiciary Act 1903 (Cth).

The Bail Act contains a basic presumption that an accused person is entitled to bail. However, like most rules, there are exceptions (see: "Grounds for refusal of bail", below). The burden of proof shifts depending on the nature of the exception.