Roger Then, 29, of Paterson, appeared in federal court in Newark Tuesday after pleading guilty to misprision of felony for concealing the civil rights.
Federal Judge William H. Wall told Then that he was not receiving the prison time because he filmed the assault, but because he subsequently lied on a police report.
He will have to report to federal prison in July, and he was also sentenced to one year supervised release.
Last week, the former officer responsible for the assault was sentenced to six years in prison for that crime, as well as dealing drugs.
Ruben McAusland was also ordered to pay $32,892 in restitution.
The U.S. Attorney's office released video of the 27-year-old McAusland, on duty and in uniform, assaulting the patient at St. Joseph's Regional Hospital in March 2018.
First, surveillance video caught McAusland pushing and punching the man, who was in a wheelchair in a waiting room full of people.
Then the patient, lying in his hospital bed, tells the officer "do it" before McAusland slaps him twice across the face so hard that blood sprays onto the bed. The man had an eye injury that required surgery.
The patient, identified as Andrew Casciano, has filed a $4 million lawsuit against the city.
McAusland pleaded guilty last June to possessing drugs with the intent to distribute and depriving the patient of his civil rights.
Prosecutors say McAusland distributed heroin, crack cocaine, powder cocaine, and marijuana on multiple occasions to someone who was cooperating with law enforcement.
In some cases, McAusland stole drugs from a crime scene while on duty.
The Associated Press contributed to this story.
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