Upon arrest, or upon appearance without arrest in response to citation or summons, or at any time before trial, before or after arraignment, the defendant shall be eligible to be released upon giving bail for his appearance in an amount and upon conditions fixed by this chapter or the judge, who shall prescribe appropriate rules of court for the receipt of bail. In case of arrests made at night or under other conditions or emergency or when the judge is not available, the rules shall authorize the chief of police, or his designated representative, to accept a temporary cash bond in such amount as set on the bond schedule prepared by the court. (2000 Code § 6-124)