The police officer had already landed a couple of shots on the man in the wheelchair, a punch to the face and a shove in the back, while they were in the hospital waiting room. But there were other people around — nurses, attendants and fellow officers — craning their necks to locate the cause of the commotion.

Later, though, Paterson, N.J., Officer Ruben McAusland and his partner, Roger Then, were alone with Andrew Casciano, who was being treated after an attempted suicide. Casciano was lying in a hospital bed when he and McAusland began trading insults.

Then pulled out his cellphone and began recording video, briefly turning the camera on himself to flash a broad, toothy smile, before training it back on his partner, who pulled on a pair of latex gloves and sidled up to Casciano.

“You got the right guy today,” McAusland told him, before slapping him twice across the face. Each time McAusland hit Casciano, fresh blood spattered the white infirmary bedsheets.

“I ain’t playing with you,” McAusland said, as Casciano shielded his face.

Then’s video of that March 2018 encounter, made public last week, became a key piece of evidence in a wide-ranging federal investigation that led to the arrests of McAusland, Then and four other Paterson police officers, accused of dealing drugs, assault and an attempted coverup, among other crimes — behavior the city’s mayor called “despicable.”

“I will not tolerate any corruption anywhere in Paterson, especially not in the police department,” Mayor Andre Sayegh said in an interview with The Washington Post. “That’s why we will ensure any crooked cop will be brought to justice.”

McAusland pleaded guilty to possession and distribution of heroin, cocaine and marijuana — all of which he said he stole from a crime scene while he was on duty — and to depriving Casciano of his civil rights by assaulting him in the hospital. He was sentenced last week to 5½ years in prison.

McAusland said Casciano threw a box of medical gloves at him and he lost his temper.

“He didn’t deserve that,” McAusland told the court, the Patterson Press reported. “Nobody deserves that from a police officer.”

Then pleaded guilty to concealing the civil rights violation and was sentenced Tuesday to six months in prison. In court, Then blamed McAusland for the hospital attack, the Press wrote.

“I dreaded going to work,” Then said. “Since he was my senior officer, I had to do whatever he said, no questions asked.”

But U.S. District Judge William Walls said Then had to serve time, to set an example for other officers.

"You let us — society — down,” Walls said. “You have to pay the price so hopefully others won’t do what you did.”

The sentencing of McAusland and Then, along with the charges federal prosecutors recently leveled against four of their former colleagues, has shaken public trust in a department that employs force at a higher rate than most other agencies across the state, according to a report from N.J. Advance Media.

Sayegh has called for an independent “top-to-bottom audit” of the police department but also said the recent crimes are “not an accurate reflection of the Paterson police department.”

“Those are bad actors that we’re taking out of the equation,” he said.

The head of the department, Jerry Speziale, told The Post that he supports the audit and any other initiative that will help police improve.

“You can always do better,” he said.

He said that the investigation is an example of oversight working the right way. It was his department’s own system, which flags suspicious officer behavior, that tipped off officials in the first place, he said. Speziale then contacted the FBI, whose agents began an inquiry.

“The facts of this case are especially troubling to those of us in law enforcement,” Gregory W. Ehrie, a Newark-based FBI agent, said in a statement. “When an officer betrays the oath to protect and serve, it tarnishes the law enforcement community and puts the public at risk."

Speziale said his department employs more than 400 officers, who are relieved that their lawbreaking colleagues are gone.

He said he understands these incidents have fractured his department’s relationship with the community it polices but is committed to earning back the public’s trust. The audit will help, he said, as will the “listening tours” he has been doing lately.

But critics of the department believe it has a long way to go. Zellie Imani, an activist based in Paterson, posted the video of McAusland hitting Casciano to Twitter. It was liked and shared more than 85,000 times.

“Divest from the police,” Imani wrote. “Police violence won’t end by ‘sensitivity training’ them. Police violence ends when we end police & replace with an alternative that actually makes the public safe.”

Casciano’s lawyer relayed to the court a written statement from his client, who, he said, also won’t soon forget his last encounter with the city’s police officers.

“Ever since I got punched in the face and abused at the hospital I have been having a very hard time,” Casciano said in the statement, which was shared with local media. “The officers who abused me have engraved a negative memory that haunts me throughout the day.”

In recent years, Paterson — New Jersey’s third-largest city — has not only grappled with corruption charges in the police department, but also in the highest rungs of local government. Its former mayor, Joey Torres, was sentenced to five years in prison for public misconduct after he directed city employees to renovate his daughter’s business. He was released in December, after serving less than 13 months behind bars.

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