A 37-year-old New York Police Department officer pleaded not guilty Tuesday to assault and other charges levied after a bystander captured a Brooklyn tussle on film with a mobile phone.

"Police officers put their lives on the line every day to keep us all safe. However, this defendant allegedly stomped on the head of a suspect as he lay on the ground, which is unacceptable for a police officer,” Brooklyn District Attorney Ken Thompson said in a statement.

Officer Joel Edouard faces up to a year in jail if convicted. He was released on his own recognizance and has been assigned desk duty.

The authorities said that in July, Edouard and his partner saw 32-year-old Jahmiel Cuffee allegedly drinking alcohol while in possession of marijuana. Cuffee allegedly resisted arrest, and a tussle began as more officers arrived on the scene in the Bedford-Stuyvesant neighborhood.

Prosecutors said in a statement [PDF] that the indictment was brought, in part, because of an onlooker's mobile-phone video recording of the July 23 incident.

The District Attorney said that, according to the investigation, a witness to the incident captured a cell phone video which depicts Cuffee on the ground, face down and being handcuffed. Also depicted on the video is Officer Edouard briefly pointing his gun at Cuffee, walking away from the scene of the arrest and then walking back and stomping on Cuffee's head as he lay on the ground. Cuffee’s head then hit the concrete, causing him to suffer abrasions and later headaches.

The defendant's attorney said the short video doesn't tell the real story. "The act, so-called kick, was part of the arrest process and to attempt to get his hand in custody so he could be handcuffed," attorney Stephen Worth said. "It’s not a kick, we’ll leave that for trial."

The defendant's next court date is March 24.

The resisting arrest charge against Cuffee has been dropped.