It's not uncommon for DC Comics' most famous Green Lantern, Hal Jordan, to fight his teammates on the Justice League. Strange, cosmic scenarios occasionally interfere with the Emerald Knight, leading him to fight his allies on the Justice League or even other members of the Green Lantern Corps. At the same time, Hal Jordan is known for his willpower, more so than any other DC character. When facing unstoppable odds, Green Lantern is usually on the front lines.
The Green Lantern Corps has several members from Earth, like John Stewart, Kyle Rayner, Jessica Cruz, and several others. However, Hal Jordan remains the most important to DC Comics continuity. He may also have the strongest willpower in the DC Universe. Hal constructed his own power ring from his sheer will in Robert Venditti and Ethan Van Sciver's Hal Jordan and the Green Lantern Corps: Rebirth one-shot. Although he's not the most obnoxious Green Lantern (that honor goes to Guy Gardener), he does get into trouble a lot. Still, Hal Jordan constantly reminds readers why the Justice League needs him.
During the Silver Age series from 2000, in Silver Age: Green Lantern #1 (by Kurt Busiek, Brent E. Anderson, and Joe Rubenstein), Hal Jordan faces the Injustice League in the bodies of the Justice League. Hal Jordan gets stuck inside the mind of Sinestro, which provides the heroes an unsuspected advantage. Not only does Hal already have experience with a power ring, but he's also controlled the power of fear before. Hal harnesses the power of Parallax, the embodiment of Sinestro's yellow light, in Emerald Twilight. Hal Jordan makes quick work of the League as Sinestro, even a Superman with Lex Luthor's mind. Hal explains that none of these villains have experiences like those of the heroes.
As for Sinestro in Hal's body, for once, the weakness to the color yellow comes in handy. Because Silver Age: Green Lantern presents itself as a tale from the Silver Age of comics (1956-1970), some classic powers and weaknesses get implemented. Although it's been somewhat retconned, Green Lantern can't use his power ring against anything yellow during the Silver Age. This isn't just in terms of Sinestro's power ring either; whether it be a Sinestro construct or a Tonka truck toy, Hal Jordan's ring is rendered useless.
Back in the original Green Lantern: Rebirth from 2004-2005, Parallax is revealed to have been trapped within the Central Power Battery at Oa until Hal released the creature in Emerald Twighlight. This secret becomes the reason why Green Lanterns can't use their power on anything yellow. Silver Age: Green Lantern happens while Parallax is supposedly in the Central Power Battery, explaining why Hal can easily defeat Sinestro. Hal is finally the one with no restrictions and actually defeats the Sinestro-controlled Hal Jordan faster than the other Leaguers, with one punch.
For once, instead of being vastly underpowered against his main villain, Green Lantern defeats Sinestro, and the rest of the Justice League, in a satisfying way. Even though Hal fails in the end, it wasn't when he was in control of Sinestro's mind. Hal uses the Central Power Battery while reciting the famous Green Lantern oath, bringing the heroes back to their proper bodies. However, this ironically weakens Hal after Luthor uses the Battery to knock out the connected minds of the entire Green Lantern Corps. The heroes eventually make a triumphant return and win in the end, but Hal's epic battle with the Justice League in Silver Age: Green Lantern is definitely one for the books.