The Snapchat app is seen on an iPhone 5s. (Andrew Harrer/Bloomberg News)

The video was humiliating and racist, and it had spread to other students at the speed of the Internet. So the black teenager who was called racial slurs while he ate chicken took matters into his own hands, with violent results.

It was early October, a few weeks after the start of classes at Saucon Valley High School, 75 miles north of Philadelphia. The 16-year-old student was at a pep rally, participating in a chicken wing eating contest, his attorney said.

Nearby, a white student, a 14-year-old underclassman, pulled out his phone and started filming.

He titled the video, “His welfare check canceled,” and provided narration, according to the Morning Call:

“So there’s a chicken wing eating contest here. This f—— n—– is taking his time. He’s getting free f—— chicken, you n—–. It has been a minute and he’s on the same f—— wing. Oh, now the black kid is taking the wings back up to his seat. What, what are you that broke?”

The white teenager goes on to make remarks about the black student being on welfare. He talks about his African features and his love of KFC.

Then he Snapchatted the video to his friends. And they shared it with their friends. By the end of the pep rally, the video had made its way to its subject.

The severity of what happened next depends on who’s telling the story.

District Attorney John Morganelli described it as “a pushing match, and the black student kind of got the better of the other student.” He declined to release either teen’s name because they are minors. The black teen’s attorney, Gary Asteak, said the nurse sent the 14-year-old home with three bumps on the head.

But the 14-year-old’s attorney described a brutal confrontation.

“As offensive as the video was, physically assaulting someone is worse,” Michael Moyer told the Morning Call. “In school. In the middle of the day. With teachers standing around.”

The boy’s father, seeing his injuries, called police, according to the DA’s office.

The black teen, whom Morganelli described as a “high-achieving” honor student, was charged with simple assault, disorderly conduct and harassment.

The 14-year-old, on the other hand, was suspended from school, but not charged.

The case elevated racial tensions in Northampton County, where 88 percent of residents are white and 6.4 percent identify as black. Many thought it unfair that the white student, who filmed and spread the video, escaped legal consequences while the black teen faced a judge.

Among the critics was Asteak, who told The Washington Post that his client reached a breaking point after the school didn’t punish previous episodes of racist bullying.

“The question is not whether the 14-year-old deserved a whupping for what he said, but whether the authorities were sensitive to the fact that he also committed an offense,” Asteak said. His client “had been called the n-word walking down the hall. He’s been taunted. This group that calls themselves the rednecks threw a Confederate flag over his shoulder and mocked him,” he said.

“When the authorities are blind to this kind of behavior, it’s like a cancer that continues to grow without treatment,” he said.

Asteak even questioned whether President-elect Donald Trump’s comments on the campaign trail played a role. “The subject of political correctness became a talking point,” he said. “It suddenly became okay to do this kind of thing.”

Asteak approached District Attorney Morganelli in court one day.

“He was here on another matter, and he asked if I’m aware of the case,” Morganelli said. “I’m the elected DA, I don’t usually see juvenile court stuff all that often . . . but when I saw [the video] I thought, Jesus, this is really bad. I inquired about why there weren’t charges brought against the white male.”

On Dec. 8, he announced that he was opening an investigation of the case to see whether the white teen should be charged with a hate crime. On Tuesday, he announced that the boy would be charged with cyber-harassment and ethnic intimidation.

He told The Post that he’s pushing for both students to be put into diversion programs that would expunge their records if they complete the terms of their probation.

The result is more fair given the circumstances, Morganelli said, although he said the announcement about charges against the white teen has brought out a different set of critics.

“I did get a lot of phone calls from, I guess I’d call them kooks,” he said. “Apparently, this stuff gets circulated on some crazy websites. I got a phone message here that said ‘Morganelli, you hate white people. You’re an n-word lover.’ ”

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