Batman once gave Superman the go-ahead to murder Lex Luthor in cold blood, adding that he would help the Man of Steel cover up the crime. What would have made the killing even worse is the fact that Luthor was President of the United States at the time. If Superman had followed Batman’s advice, he would have been committing treason by assassinating a sitting Commander-in-Chief.

The shocking exchange comes in the fifth issue of 2003’s Superman/Batman series written by Jeph Loeb and drawn by Ed McGuinness. The first story arc, “Public Enemies,” revolves around a Kryptonite asteroid heading towards Earth, promising to wipe out all life on the planet. Then-President Lex Luthor publicly accuses Superman of being responsible for the asteroid and offers a billion-dollar reward for his capture. Superman and Batman team up to both stop the asteroid and clear the Last Son of Krypton’s name. With supervillains and superheroes out to collect the bounty on Superman’s head, the two eventually fight their way into the White House where they confront Luthor.

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By the series’ fifth issue, Superman is furious that Lex Luthor has taken advantage of the asteroid situation to put a bounty on his head, as well as the fact that a villain like Luthor even became president in the first place. Disguising himself as Shazam (known as Captain Marvel at the time), Superman makes it into the Oval Office and grabs Luthor by the throat. As his eyes glow red, Batman suddenly appears next to him. In a statement that seemingly goes against his code, Bruce tells Clark, “I will not stop you. There are ways we could make it look like an accident. Or better still–as if he’d disappeared without a trace.

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Batman is not bluffing, either. He remembers a time when he was in a similar situation with the Joker and Commissioner Jim Gordon talked him down. “But I am not Jim Gordon,” he says. He adds that as evil as the Joker is, anything he has done to Gotham City is not as bad as the evil that Luthor has done to the planet. “Worse…what he does to Clark,” Batman reflects. This shows that even Batman is willing to break his “no killing” rule when it comes to protecting his friend.

Superman appears to very much consider the opportunity to rid the world of Luthor’s evil once and for all. He remembers his father teaching him, “When the fox is in the chicken house, you have to kill it…unless you plan on losing more chickens.” Killing Luthor would certainly not be a difficult feat for him: “Holding him like this–he’s so small. So frail. He would snap like it was nothing.”

Ultimately Superman decides to stick to his principles and not murder the President of the United States in cold blood. Confirming that his and Batman’s allies are safe, he tosses Luthor aside and leaves to deal with the asteroid. It speaks to how evil Lex Luthor is that even the Big Blue Boy Scout would consider snapping his neck. But the fact that Superman and Batman ultimately decide to step back from that line shows why they truly are the world’s finest heroes.

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