It’s a sleazy scenario that plays out in bars and clubs across the Big Apple: Everybody’s having a great time until some creep just can’t keep his hands to himself.

But early Sunday at Bar None — a Third Avenue dive in the East Village where NYU co-eds squeeze in every weekend to chug cheap Bud and dance to ’90s rock — one of these guys would finally face the consequences.

A creep put his paws all over an unwitting young woman’s boobs and backside, she said, and the victim immediately reported the sleazy moves to a bouncer.

From there, the bar did everything right — calling the police and holding the suspect in place. He even tried to run when the cops showed up.

For any other perp, that would have led to an arrest and up to a year in prison. But Hassan Salih, 36, had the ultimate free pass: diplomatic immunity. So the mid-level Sudanese attaché escaped with no charges, no court date and no consequences.

“Everyone is infuriated,” fumed a Bar None bartender. “How is it this guy gets a ‘Get out of jail free’ card?”

Salih is hardly alone. He is the latest in a long line of diplomats in New York to use the privilege to get out of serious trouble, including wife-beating and even injuring cops.

The rule, part of an international treaty dating to the 1960s, means diplomats can’t be arrested or sued in their host country — no matter what they do. “They can literally get away with murder,” said Peter Spiro, a professor of international law at Temple.

Even if a diplomat stands in the middle of Fifth Avenue and shoots somebody, the cops can’t charge them, he said. The most the United States can do is ask their home country to waive immunity — which almost never transpires — or kick them out, which the feds aren’t always willing to do, according to a former city attorney.

“The State Department doesn’t always prioritize the city’s concern for safety above politics,” said Linda Wayner, a former general counsel to the Mayor’s Office for International Affairs.

As a result, New York — home to the UN General Assembly and 117 diplomatic missions — regularly witnesses dirty diplomats getting off the hook for shocking crimes.

In July, Afghan diplomat Mohammad Yama Aini was protected after he allegedly bashed his wife so badly that she ended up in the hospital.

Aini denied he’d done anything wrong, but police sources said she’d reported being punched and slapped. “I’m sure the hospital victims’ services referred her to get help. But if he’s not arrested, what can you do?” a source said at the time.

In January, another accused Sudanese sleazebag, Abdalla Ali, was busted allegedly grinding his crotch on a woman on a 4 train — in full view of transit cops — but faced zero consequences.

Perhaps most notoriously, German Joachim Haubrichs got away with allegedly punching his wife in October 2016.

His spouse, Henna Johnson, spoke openly with The Post about his allegedly violent and controlling ways at the time — she said he became enraged because she was speaking on the phone after 7:30 p.m. and he enforced a strict bedtime.

Neighbors said it was a regular occurrence.

“He hits her real hard. He’s broken a bunch of her bones in her face. He only hits her in the face. Black eyes. I’ve seen a million of them,” said a resident of their Upper East Side building.

But police couldn’t even remove Haubrichs from the home — they advised Johnson to go to a domestic-violence shelter.

Cops can’t even do anything when they’re the victims — as when blind-drunk Zambian government official Langford Banda crashed his car into an NYPD van in 2015, injuring two officers.

“He was a total mess,” a law enforcement source told The Post at the time. “He got off because he’s a diplomat. Not our choice.”

It can be very “frustrating” for the arresting officers, says Joseph Giacalone, a retired NYPD sergeant and adjunct professor at John Jay College of Criminal Justice.

“The procedure is: As soon as diplomatic identity is proven, police have to let them go,” Giacalone said.

“Sometimes, it’s all done within 15 to 20 minutes.”

Immunity also means the city is powerless to make diplomats pay parking tickets, which has allowed them to rack up more than $16 million in unpaid fines since the 1990s.

Egyptian envoys are the worst offenders by a large margin — with almost $2 million in debts — followed by Nigeria, Indonesia and Brazil, according to a 2015 analysis.

One Egyptian car alone amassed more than $223,000 from almost 2,000 unpaid tickets between 1997 and 2015.

The rogue parking dropped off heavily after 2002, when the State Department started refusing to reregister cars with large outstanding ticket debts — but most countries still haven’t paid their fines.

Diplomatic immunity cuts both ways, and it has also spared plenty of Americans from the slammer while abroad.

It’s rare for US diplomats to be busted groping strangers or beating their wives, Spiro says, but they could otherwise face all sorts of trumped-up charges from foreign governments.

In 2008, then-Ambassador to Bolivia Philip Goldberg was accused of spying and declared persona non grata. Venezuela expelled Ambassador Patrick Duddy in solidarity.

In 2011, then-US Ambassador to Ecuador Heather Hodges was expelled after she expressed concerns about police corruption there.

“Diplomatic immunity disables states from framing diplomats,” Spiro said.

Foreign officials caught behaving badly in the States are also often whisked back to their home countries to avoid embarrassment, police sources told The Post.

And governments sometimes work with local officials behind the scenes, according to Wayner — in cases of child abuse, they have refrained from insisting that Children’s Services hand kids back.

Still, it’s hard to keep the big picture in mind when you’re fighting crime.

“For police on the scene, they’re not thinking of our guys in Pakistan. They’re just thinking about what’s happening on Fifth Avenue,” Giacalone said. “You’re saying, ‘This is not fair.’ ”