A 16-year-old boy who opened fire outside Rosemary Anderson High School last December and wounded four students was sentenced Wednesday to 10 years in prison.

Wearing chains around his waist and looking nervous, Marquise Murphy pleaded guilty to attempted murder, first-degree assault, second-degree assault and unlawful use of a firearm in Multnomah County Circuit Court.

It was five months after bullets flew and blood spilled outside the North Portland alternative high school in the gang-related shooting.

"I apologize to the families that are involved," Murphy said.

Prosecutor Glen Banfield said in fashioning Murphy's sentence, the state took into consideration that he had no prior criminal history -- unlike the two other defendants in the Dec. 12, 2014, barrage.

The plea agreement allows Murphy to be released after 8 1/2 years in prison if -- on his 25th birthday -- it's determined that he has reformed while in youth prison.

His defense attorney, Russell Barnett, said he didn't believe the evidence proved his client was the shooter, noting that some witnesses had said Murphy's brother was the gunman. Nonetheless, Barnett said he recommended his client agree to the plea deal because he could receive more time in prison if convicted after a trial.

But Banfield said two witnesses pointed to Marquise Murphy as the shooter. And there were "copious amounts" of other evidence on Facebook and elsewhere that implicated Marquise Murphy, the prosecutor said.

Murphy's 22-year-old brother, Lonzo Murphy, insisted he wasn't a part of the shooting during an earlier hearing Wednesday. Prosecutors said Lonzo Murphy accompanied his brother to the high school that day, so they pursued criminal charges under an "aiding and abetting" theory.

"I didn't do anything," Lonzo Murphy said.

Before pleading no contest to five counts, Lonzo Murphy told Judge Stephen Bushong that the prosecution's aiding-and-abetting theory didn't seem fair.

The judge told him he didn't have to plead if he didn't want to, but Lonzo Murphy said he wanted to accept the deal because he was worried he would be convicted at trial. He pleaded no contest to attempted first-degree assault, second-degree assault, third-degree assault, conspiracy to commit first-degree assault and being a felon in possession of a firearm.

Lonzo Murphy was sentenced to 7 1/6 years in prison. Marquel Dugas, an 18-year-old friend who accompanied the Murphy brothers to the high school, was sentenced to 8 1/3 years in prison.

Dugas pleaded no contest to four counts, one for each victim: first-degree assault, second-degree assault, third-degree assault and unlawful use of a weapon. He also was found to be in violation of his probation.

Dugas' attorney, Ernest Warren, said his client feels remorse and regrets that the students were hurt.

Dugas declined to make a statement.

None of the victims attended any of the hearings.

Authorities say that on the morning of the shooting, all three took the No. 72 TriMet bus to the area of North Killingsworth and Albina Avenue, just steps from the high school, according to a probable cause affidavit filed by the prosecution. As students began to step outside for the noon lunch hour, Lonzo Murphy saw a young man named "David" walk out of the doors of the school and move "his hands towards his waist like he had a gun," the affidavit said.

Marquise Murphy then pulled out a 9mm Ruger handgun and opened fire, his older brother told police. According to the affidavit, witnesses said they heard Marquise Murphy "exclaim that he was about to become a Blood" before he began shooting. Police said Lonzo Murphy and Dugas are members of the Lincoln Park Blood gang.

David Jackson-Lyday -- 20 and a member of the Columbia Villa Crips, police said -- was shot twice in the abdomen. Taylor Zimmers, 16, suffered wounds to the chest and abdomen. LaBraye Franklin, 17, was struck in the upper back. Olyvia Batson, 17, suffered a graze wound to her left heel.

After the shooting, police found Lonzo Murphy next to the silver-and-black 9 mm Ruger handgun used in the shooting and said he had tried to hide it outside his mother's apartment complex.

Two days before the shooting, Marquise Murphy recorded a cellphone video showing him waving the gun and identifying himself as being associated with the Lincoln Park Bloods, according to the affidavit. He warned the Columbia Villa Crips that "it's war time, be ready and stay strapped because we coming with full clips," the affidavit said.

A fourth man charged in relation to the case, Geno Malique King, was accused of trying to help Marquise Murphy flee the state by driving a car toward Las Vegas. King, 19, was charged with trying to elude police who caught up to him in the Salem area. In March, he pleaded guilty in Marion County Circuit Court, and was sentenced to 1 1/2 years of probation.

King also was charged in Multnomah County Circuit Court with hindering prosecution and gun-related charges. In March, he pleaded guilty to unlawful possession of a firearm and was sentenced to two years of probation in Multnomah County after a gun was found in the car.

-- Aimee Green

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