Wookiee culture placed a high value on the use of their claws for peaceful, productive reasons only. Thus, any Wookiee who lashed out against another Wookiee (or any other living being) with their claws was deemed to be a madclaw. The title was a grave dishonor, since the Wookiees viewed the use of claws for anything other than tools as feral, and madclaws were usually sent into exile.
To date, the only madclaw to become famous throughout the galaxy was Zaalbar, one of the companions of the Jedi Revan. He lashed out at his brother, Chuundar, after discovering he'd been cutting deals with Czerka Corporation slavers. His father, the chieftain Freyyr, didn't believe him, and he was exiled. He later received a pardon.
The albino Wookiee Tojjevvuk also dishonored himself by using his claws to attack Chewbacca when they fought over Mallatobuck, but since that battle ended with Chewbacca hurling Tojjevvuk to his death in the Shadowlands, Tojjevvuk was never brought to justice by his people and formally dishonored with the title madclaw.
- The Complete Star Wars Encyclopedia (see mad-claw)