A comic book science fiction story, published in Weird Fantasy #18 in April 1953, and later reprinted in Incredible Science Fiction #33 in February 1956. Both magazines were published by EC Comics. The story was written by Al Feldstein and illustrated by Joe Orlando

Let's review the plot -- the full plot, with spoilers -- first: 

Tarlton is a human from Earth's Galactic Republic paying a visit to Cybrinia, a planet of robots. They have asked to join the Republic, and Tarlton is here to judge whether or not they are worthy of becoming members. Tarlton -- he keeps his helmet on for most of the story, perhaps because there is no breathable atmosphere on the planet -- is guided through the robot society by an orange robot assigned to show him the advanced civilization of Cybrinia. The robot shows Tarlton the clean, modern city, with democratically elected representatives, the free charging stations. Tarlton watches how the robots are constructed and programmed. 

But it's also clear the robot society is far from ideal. The orange robots are at the top of this civilization, with the best charging stations, the best programming, the best jobs. Blue robots, on the other hand, must live in slums. They work bad jobs they aren't allowed to retire from. Their charging stations are low-grade, and their programming is limited. They even have to sit at the back of the city's buses. In fact, the blue robots are exactly the same as the orange robots -- same designs, same alloys, same components. The only differences are the colors on the outsides and what sort of programming is allowed for each. 

Well, we have to keep them in their place, protests the orange robot. It's been like this since before I was constructed! What do you want me to do?! I'm only one robot! 

No, Cybrinia won't be allowed membership in the Galactic Republic. But Tarlton encourages the robots to keep trying, telling them that thousands of years ago, human on Earth realized they all had to live together before they could improve their lives, and robots can learn to do the same. 

Tarlton returns to his ship, finally removing his helmet so the reader can see what he looks like. The narration reads: "And inside the ship, the man removed his space helmet and shook his head, and the instrument lights made the beads of perspiration on his dark skin twinkle like distant stars..."

This is a really nice story, and a wonderful example of the high quality of work produced by EC. It's a story with a lot of dialogue and a lot of captions, but it still moves along at a good pace. The messaging is a bit heavy-handed and unsubtle, particularly the blue robots forced to ride in the back of the bus. Of course, the early 1950s were a time more people were learning of the horrors of the Jim Crow South and becoming more outraged by it. 

What seems to be a weakness of the art is the almost complete lack of truly human figures we can identify with. The robots have immobile faces and cannot display their emotions, and Tarlton wears his space helmet almost constantly, making his face even less human in appearance than the robots. But this weakness vanishes with Joe Orlando's final panel. We've spent seven pages looking at non-human figures, and finally, we see a beautiful and perfectly human face. That's who we've been identifying with this whole time, and Orlando pulls out the stops to show us this handsome Black man, gazing out on the universe, his face dotted with perspiration. Ultimately, he's all of us, he's someone we should aspire to be, we're proud of his wisdom, and we're proud of the humanity we share with him. 

The original 1953 story got overwhelmingly positive feedback from readers. But EC reprinted two letters they said they were especially proud of. The first was from J.B. Kenny, principal of the School of Industrial Art (now the High School of Art and Design) in New York City. He requested 35 extra copies of the issue, saying "Our students would profit greatly from seeing the work of Mr. Orlando, as well as benefitting from the excellent theme..." (EC sent them 50 copies instead.)

And another letter came in from Ray Bradbury himself. He said, "I realize you have been battling, in the sea of comics, to try to do better things. You have certainly succeeded in JUDGMENT DAY, which should be required reading for every man, woman, and child in the United States. You've done a splendid thing here, and deserve the highest commendation."

The Comics Code Authority didn't exist in 1953, but they did in time for the reprint in 1956. And the guy in charge of the CCA, Judge Charles Murphy, hit the roof about this story. He'd already nixed an original story EC had planned for the issue because it also starred a Black person. Murphy demanded the final panel of the reprint needed to be changed to make Tarlton white. There wasn't anything in the CCA rules that said characters had to be white -- but Judge Murphy was a racist piece of shit, so that was all he cared about.

Feldstein told Murphy the entire point of the story was that Tarlton was Black, and emphasized that everyone knew the CCA was riding EC so hard because they were trying to run them out of business. Feldstein then told EC publisher William Gaines about the call, sending Gaines into a rage. He called Murphy back and threatened to sue the CCA and hold a press conference about the incident. I'm not sure Gaines would've had any standing to sue, but the publicity for the Comics Code, even in the 1950s, would've been catastrophic

After this, Judge Murphy suggested instead that EC just take off the beads of sweat on Tarlton's face, which got both Gaines and Feldstein to yell "Fuck you!" into the phone before Murphy hung up. 

Incredible Science Fiction #33 ended up being the last comic book EC published, but it ran with "Judgment Day" uncensored in its pages. EC soon put all its efforts into Mad Magazine, which didn't fall under the stern and racist gaze of the Comics Code Authority. 

Today, the Comics Code Authority is dead. Judge Charles Murphy is also dead, and remembered only as a racist bigot. Both are much deader than EC Comics or "Judgment Day," which are still remembered and revered by comics fans.

Research:
Wikipedia
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Reprint of the story