An attorney's badge is a defense lawyer's main piece of identification for legal purposes. It has a number on the back that denotes an ID number for its owner and is mainly composed of silver. However, one can fool the court using a fake badge, as Furio Tigre once did with a cardboard version.
The attorney's badge can almost always be found in the court record, as a defense attorney requires it as proof of their occupation. Defense attorneys appear quite proud of their badges, although Phoenix Wright in particular seems to have been very fond of his. Attorneys occasionally need to present their badge to offer to take people's cases, though usually Wright just flashes it proudly whilst his audience makes a disparaging remark or dismisses it entirely. In contrast, prosecutors also have badges, but rarely wear them since they are state-appointed.
Phoenix Wright has lost his badge twice. The first time was when Money, a monkey performing at the Berry Big Circus, stole it. The second time was when Wright got disbarred; he lost his badge and had to investigate without it. Wright also once lent it to Miles Edgeworth, so that the latter could investigate on his behalf and take his place in court.