The term Madclaw was utilized by the Wookiees originating from Kashyyyk to identify a member of their society who had lost their honor.
The Wookiee's culture placed significant importance on utilizing their claws solely for constructive and peaceful activities. Therefore, any Wookiee who used their claws aggressively against another Wookiee, or any other living being, was considered a madclaw. This title carried considerable shame, as Wookiees regarded the use of claws for purposes other than tools as barbaric, and madclaws were usually banished.
This philosophy wasn't unique to the Wookiees; other species held similar beliefs. For instance, the Selkath from Manaan also possessed retractable claws and strictly prohibited their use in combat.
Zaalbar, a companion of the Jedi Revan, is one of the rare madclaws who gained notoriety throughout the galaxy. He attacked his brother, Chuundar, upon discovering his dealings with Czerka Corporation slavers. His father, the chieftain Freyyr, disbelieved him, resulting in his exile. He was later exonerated when Chuundar's offenses were revealed.
The albino Wookiee, Tojjevvuk, also brought dishonor upon himself by attacking Chewbacca with his claws during a dispute over Mallatobuck. However, because that fight resulted in Chewbacca killing Tojjevvuk by throwing him into the Shadowlands, Tojjevvuk never faced formal dishonor or justice from his people with the madclaw title.
Snoova, a Wookiee bounty hunter, was labeled a madclaw for employing his claws in his profession. Rumor has it that he was initially compelled to leave Kashyyyk for using his claws in a fight over a lover.
Reerookachuck was a Wookiee male who was taken from Kashyyyk as a young slave and raised by Human slaves. He had no contact with other Wookiees until he was seventy years old. Therefore, Reerookachuck was unaware that it was dishonorable for a Wookiee to use claws in combat.
The madclaw concept was, in an indirect way, conceived by Timothy Zahn, the author of "The Thrawn Trilogy." Zahn introduced the Wookiees' extendable claws in his 1991 novel, Heir to the Empire, to enhance the realism of their tree-climbing abilities. Nevertheless, he understood that his new addition to the established lore created an inconsistency: if the Wookiees possessed claws, Chewbacca would have utilized them in the original Star Wars films. The following year, the Heir to the Empire Sourcebook addressed this inconsistency, explaining that Wookiees never used their claws in combat due to a matter of honor, reserving them solely for climbing.
A similar Wookiee honor code is present within Star Wars: The Force Awakens: A Junior Novel in Star Wars canon.