Erik Jansen, left, partner of killed NYPD Officer Brian Moore,...

Erik Jansen, left, partner of killed NYPD Officer Brian Moore, testified Oct. 23, 2017, at the trial of Demetrius Blackwell, who is accused of killing Moore. Credit: Uli Seit

Standing in the well of a packed Queens courtroom on Monday, a former NYPD officer pointed at Demetrius Blackwell and told jurors that was the man who shot and killed his partner in 2015.

“Any doubt that’s the shooter?” Queens Assistant District Attorney Daniel Saunders asked the witness, Erik Jansen.

“No, sir,” said Jansen, who now works for the Suffolk County Police Department.

Jansen, the third prosecution witness to testify at Blackwell’s trial in Queens County Criminal Court in Kew Gardens, said Blackwell shot at him and his partner, Brian Moore of Plainedge, on May 2, 2015 immediately after they stopped and questioned Blackwell for allegedly attempting to conceal “something” on his body.

Blackwell, 37, is on trial for first-degree murder, attempted murder and other charges. If convicted of first-degree murder, Blackwell faces life in prison without the possibility of parole.

Jansen said he and Moore were seated in their unmarked police car when Blackwell fired two, possibly three, shots at them. They both ducked, but Jansen said Moore, who was slumped over the steering wheel, never lifted his head up again.

After he radioed for help, Jansen said he went to help Moore, who was bleeding from the head, but was still breathing. Jansen took off his shirt, and put it under Moore’s head to stop the bleeding.

“I kept trying to tell him to wake up, but he was unresponsive,” said Jansen, who was not hurt.

Richard Tarver, one of the first officers at the scene, said he drove Moore to Jamaica Hospital Medical Center, going 100 mph, blowing red lights, driving on the grass and down the wrong way of a one-way street.

“He was moaning and just seemed like he was in a lot of pain,” Tarver said, describing when he helped carry Moore into the marked police vehicle minutes earlier.

Sgt. Christopher Noll, who was riding in the back seat with Moore, testified that he removed Moore’s bulletproof vest, clothes and shoes in an attempt to find the wound.

At one point, Noll said he unknowingly pressed his hand against a second wound on Moore’s face. He said the wounded officer “began to scratch my arm.”

Moore, 25, died two days later.

Authorities said Blackwell, who fled, was arrested about an hour and half after the shooting. Investigators found a silver handgun, a Taurus Model 85 revolver, in the backyard of a house not far from where the shooting happened. A prosecutor said DNA evidence discovered on it linked Blackwell to the weapon.

Blackwell’s attorney, David Bart, had said his client suffered from epilepsy and had head surgery two years before the shooting. In his opening statement, Bart said he planned to raise the issue of Blackwell’s mental health.

Bart is scheduled to question Jansen Tuesday when the trial resumes before state Supreme Court Justice Gregory Lasak.

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