The "young partner" of Vel Quennar, the esteemed Lexorian attorney who is appointed to defend Superman when the Man of Steel is brought to trial on the planet Lexor on the charge of having deliberately murdered Lex Luthor, Lexor's greatest hero.
Garn Abu is a hot-headed young attorney who, like most Lexorians, hates Superman and assumes he is guilty. He unsuccessfully urges Vel Quennar to withdraw from the case, on the ground that Quennar's career will suffer if he defends a murderer like Superman (Act No. 318/1, Nov 1964: "The Death of Luthor!").
Once the trial gets under way, however, Garn Abu works dedicatedly in Superman's defense, arguing that the Man of Steel was temporarily insane when he murdered Luthor. Although Superman himself demolishes this defense by hewing to his claim that Luthor's death was an accident, he is ultimately pronounced not guilty and released from custody when it is discovered that Luthor has not died at all, but has merely been in a "deathlike trance" induced by a "coma drug." Garn Abu is alternatively rendered as Garn Abo (Act No. 319/1, Dec 1964: "The Condemned Superman!"). (TGSB)