Marcquis Walker-Williams claimed that he just wanted to "catch a body" on July 10, 2007. In the parlance of the teen's world, that meant to assault a complete stranger, then run away.

Unfortunately for Walker-Williams, his plan fell apart when a neighbor lady saw him put a choke hold on Kwok Wai Ho on an Oxford Circle sidewalk. She screamed for him to let the man go. Walker-Williams did, and the 69-year-old victim fell and struck his head on the concrete.

Ho, who was taking his evening stroll through his neighborhood when he was attacked, died of head injuries a week later at Thomas Jefferson University Hospital.

Walker-Williams, 19, sat quietly yesterday as a handful of the friends he was with that July day told a Common Pleas Court judge and jury that he was the one who asked them: "Y'all want to catch a body?"

The witnesses testified that they declined the offer but that Walker-Williams still grabbed Ho as he walked along Greeby Street, near Loretto Avenue.

He is charged with general murder, meaning that if found guilty the jury will decide what degree of murder was committed.

Defense attorney Jamie Egan said that although he makes no excuses for Walker-Williams' behavior, his client has been overcharged.

"What Marcquis Walker-Williams did on July 10, 2007, was stupid, thoughtless, callous, careless and juvenile, but it was not murder," he told the jury on Tuesday, the trial's opening day.

Assistant District Attorney Leon Goodman said that the case against Walker-Williams is solid.

"He announced what his intent was, he announced what he was going to do and he did what he was going to do," he said during a court break yesterday.

The evidence, Goodman added, will show that Walker-Williams also planned to rob Ho.

That contention was supported by Kyhree Greennagh, who was among a group of about eight teenage boys who were walking to a Rite Aid when Walker-Williams allegedly asked about "catching a body."

"He was attempting to rob him; he didn't mean to kill him," Greennagh said on the witness stand yesterday.

Greennagh said that he cautioned Walker-Williams against targeting Ho because the neighbor was on her front porch.

Maurice Kemp, 19, said that he also thought that it was a bad idea because Ho - who was of Chinese descent - was a friendly man who regularly walked the Northeast community.

"I used to see the man every day, walking with his hands behind his back," Kemp said. "He used to say 'hi' to me. He was cool."

Though he defined "catching a body" as choking someone and going through their pockets, Kemp said that Walker-Williams never mentioned robbing Ho.

Tyhara Cobb, 16, who was also in the group of boys, said that he had warned Walker-Williams: "Don't touch him, he's too old."

But, after the group had passed Ho, who was walking in the opposite direction, Walker-Williams turned and walked behind the elderly man, Cobb said.

He said he then saw Walker-Williams clutching Ho's neck.

"I was stunned," Cobb told the jury. "I was shocked."

The trial got off to a rocky start Tuesday, when Judge Shelley Robins New ejected three spectators from the Criminal Justice Center after they were overheard in a hallway talking in threatening tones about witnesses.

She warned them that if they are spotted in the building during the trial, they would be in contempt of her order and jailed for six months.