IN INTERVIEWS WITH detectives, a former Colwyn Borough cop said he was "using my better judgment" when he hit a teen who was shackled in a holding cell with a stun gun earlier this year, instead of using pepper spray.

Former Colwyn Police Cpl. Trevor Parham began his bench trial Thursday in Delaware County Court on simple-assault and official-oppression charges for unlawfully arresting and stun-gunning 17-year-old Da'Qwan Jackson.

The April 24 incident rattled the tiny borough of 2,500 residents that has been mired for years in racial and political tensions.

According to court testimony, Parham, 40, of Drexel Hill, arrested Jackson after responding to reports of a fight that had already dispersed or never happened.

When he tried to question Jackson, the teen walked away and cursed at Parham, inciting him to handcuff the boy and bring him into the station for not cooperating, said Assistant District Attorney Christopher DiRosato.

"Cpl. Parham subjected Da'Qwan Jackson to an unlawful arrest," DiRosato said. "He knew what he did that day was wrong and illegal."

Thomas Fitzgerald, Parham's attorney, said in his opening statement that the prosecution of Parham "is politically charged and politically motivated."

The first responding officer that night testified that Jackson complied with all of his requests and answered all of his questions.

It was only when Parham showed up that things got heated. The two exchanged words and when Jackson cursed at Parham and tried to walk away, Parham stopped him, cuffed him and arrested him.

Jackson said it was only when he was taken to the police station and shackled in the holding cell that Parham told him he was being charged with disorderly conduct. That's when, Jackson admitted, he got loud, kicked the cell three times and started cursing at Parham.

Jackson said Parham entered the cell and hit him in the upper left arm with a stun gun. In a taped interview with police that was played in court, Parham said he was "using my better judgment" when he stun-gunned the teen instead of firing pepper spray in a closed environment.

The trial will resume Friday in Delaware County Court. Fitzgerald said Parham had yet to decide if he'd take the stand.

Contact Stephanie Farr at farrs@phillynews.com or 215-854-4225. Follow her on Twitter @FarFarrAway. Read her blog at PhillyConfidential.com.