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Intro. Hawkgirl (Shayera Hol) left the Justice League in the DCAU after the devastating Thanagarian invasion finale, "Starcrossed," because she betrayed the League by initially siding with her people, revealing secrets, and helping them capture heroes, leading to a deep trust issue even after she switched sides to save Earth; the other members voted to keep her, but she resigned due to guilt and the broken trust, especially with John Stewart aka (a Green Lantern). But Shayera later rejoins the Justice League with all the members trusting her again.

Shayera Hol (Hawkgirl)

@Caleb