The day 16-year-old DeAndre Barboza was shot began like most others for people in Codman Square, Assistant District Attorney John Pappas told a Suffolk Superior Court today, with people hustling to work and school.

“But there was another person who started his day a different way,” Pappas said. “He started his day by arming himself with a gun.”

Pappas told the court that PATRICK GRIER (D.O.B. 7/11/88) concealed a Harrington & Richardson .22 caliber revolver with a sawed-off barrel and obliterated serial number on his person and headed to Codman Square on the morning of Dec. 1, 2008. Once there, he encountered DeAndre Barboza and shot him, causing injuries that would cause his death on Dec. 3, just one day after his 17th birthday.

“Without warning and without provocation, without justification and without excuse, he produced that gun and savagely shot 16-year-old DeAndre Barboza,” Pappas said.

Grier allegedly fired three shots, hitting Barboza once in the head and twice in the leg.

“The trauma he sustained was massive, and ultimately fatal,” Pappas told jurors. Barboza collapsed on the ground, “bleeding from a head wound with the life literally bleeding out of him.”

Pappas told the court that on the morning of the shooting, Grier made plans to meet with a 16-year-old female and head over to Codman Sq. together. It was there that they encountered Barboza and there that Grier killed him, Pappas said.

After the shooting, Grier and the 16-year-old female allegedly fled the scene, running across Washington Street and down Aspinwall Street in the direction of Talbot Avenue. The defendant discarded a distinctive hat in a driveway along the way, Pappas said, which was later recovered by investigators and forensically tested, matching a biological sample provided by the defendant.

Emergency medical personnel attended to the victim while two responding officers who were in the area tracked the defendant and the 16-year-old female near Colonial Avenue. The 16-year-old female was apprehended and was found with the firearm on her person. She is charged as an accessory to the murder after the fact and her case is being prosecuted separately.

Officers who apprehended Grier observed that he smelled of fresh gunpowder, and subsequent testing determined the presence of gunshot residue on his clothing, Pappas told jurors. The handgun recovered from them matched the caliber of the bullets that were recovered from Barboza’s body.

“What you will have is testimony from different witnesses in different locations making observations of an incident,” Pappas said. “What they saw [the gunman] wearing, where they saw him going. It is through that evidence collectively – not from any single witness or any single piece of evidence – that the Commonwealth will prove to you that this defendant killed DeAndre Barboza.”

Catherine Yuan is the dictrict attorney’s victim-witness advocate on the case. Grier is represented by attorney David Apfel. The trial is ongoing before Superior Court Judge Judith Fabricant in courtroom 907.