A judge has tossed out drug charges against a Seneca College student after finding a police officer “was evasive and contrived” in his testimony and assaulted the suspect “without justification.”

Although David Tang, 21, displayed “stoicism” about his injuries — a black eye and facial bruising — that “cannot justify police misconduct,” Ontario provincial court Justice Paul Reinhardt said in his ruling.

Reinhardt stayed ecstasy trafficking charges against Tang, although police recovered 28 grams during the arrest in a west Toronto plaza.

On the evening of Dec. 8, 2009, undercover Toronto drug squad officers arrested Tang after he handed over a plastic bag of what police believed was ecstasy in a beer store parking lot in exchange for $700, the judge said.

Tang testified he was sitting in the back seat of what turned out to be an undercover police vehicle, completing the deal, when a man opened the door.

Tang said the man, later identified as Const. Dion Monahar, pointed a gun at him and pulled him out by the jacket. The officer kneed him in the stomach, punched him in the left eye and threw him on the ground, Tang said.

Tang’s lawyer, Heather Pringle, alleged excessive force was used and that the police injury report minimized his injuries.

On the stand, Monahar said he grabbed Tang’s chest, pulled him out of the car and forced him to the ground, where he landed on his face and chest.

But Monahar’s notes did not mention the fact that he used force during his arrest, nor Tang’s injury, Reinhardt said.

“I have concluded that Const. Monahar’s testimony was evasive and contrived,” Reinhardt wrote.

Tang has established he was “assaulted without justification” by Monahar, the judge said, adding the officer “misled this court.”