SOMERVILLE, N.J. — The trial of Jayson Williams, the former NBA star accused of manslaughter for shooting a chauffeur, opened Tuesday with a defense lawyer claiming "grime and goop" in a shotgun and not drunken recklessness caused the man's death.

As Williams, wearing a black suit, a large diamond cross on his lapel and a dejected expression, looked on from the defense table, attorney Billy Martin told jurors the fatal shooting of driver Costas "Gus" Christofi was an "unforeseeable accident" that could be blamed on dirt in the weapon and a defect in its design, but not on any bad behavior by Williams.

The dirt build-up "caused that gun to go off without pulling the trigger," Martin said during opening statements in the trial.

Martin indicated that Williams himself would take the stand to describe the events as they unfolded that night.

Williams, a one-time all-star who held an $86 million contract with the New Jersey Nets, faces 55 years in prison if convicted of aggravated manslaughter. He is also accused of covering up the shooting by urging other witnesses to lie and by rearranging Christofi's body and the gun so his death appeared to be a suicide.

There is no dispute that Williams shot Christofi while giving guests, including four members of the Harlem Globetrotters, a midnight tour of his sprawling Hunterdon County mansion Feb. 14, 2002.

Jurors, however, must decide whether he was acting recklessly and with a disregard for human life when he pulled a loaded 22-gauge double-barrel shotgun from the gun cabinet in front of visitors in his master bedroom, cracked it open and then jerked it shut.

Both sides agree that, as the weapon snapped shut, it discharged, riddling Christofi's abdomen with buckshot. The 55-year-old bled to death within minutes.

Prosecutor Steven Lember told jurors Tuesday that ballistics experts will testify that Williams' finger had to be on the trigger for the gun to go off. Defense attorney Martin promised jurors his own ballistics experts would refute that claim.

'It wasn't an accident'

In addition to differing on how the gun went off, the prosecutor and defense attorney painted very different portraits of Williams and how he acted on the fatal night. Williams, his father, nephew and some friends went to a Globetrotters game at Lehigh University. He then hired a driver, Christofi, to bring four Globetrotters to New Jersey for dinner at a restaurant near his mansion.

Prosecutor Steven Lember told jurors that Williams' behavior was reckless and showed disregard for human life.

Lember told jurors that Williams turned an "evening of entertainment" into a "night of death and deception." He told the jury Williams was drinking chardonnay, whiskey and Sambuca at the restaurant and began taunting Christofi, whom he had never met, with mean-spirited remarks and curses.

He said Christofi, whom he described as a likeable guy and his company's best employee, put up with the abuse because he was a sports enthusiast who hoped to get his picture taken with Williams and the Globetrotters.

Instead, Lember said, when Williams' friends urged him to pose for a photo, Williams grabbed Christofi roughly.

"He picked him up, did a bear hug and attempted to simulate a body slam and then put him down. There was no photo," he said.

The prosecutor said that immediately before the shooting Williams "is heard to curse at Gus, and Gus, according to witnesses, rolls his eyes."

Seconds later, Lember said, Williams pointed the gun at Christofi and snapped it shut.

"It wasn't an accident at all," said Lember, charging that the recklessness of the act made it a crime.

Christofi's sister, Andrea Adams, sat behind the prosecutor in the front row of the court. A member of the prosecutor's staff put her arm around Adams' shoulders as Lember discussed the shooting.

'A big teddy bear'

When it was the defense's turn, Williams' lawyer spent most of his hour and 15 minutes describing his client in the type of glowing language usually reserved for a retirement dinner.

With Williams' wife, Tanya, who is due to deliver their second child in April, seated in the front row between his publicist and his jury consultant, Martin told panelists that Williams is a family-oriented, hardworking man known for his generosity.

Defense lawyer Billy Martin described Williams as a good-hearted person and blamed the shooting on a faulty gun.

He is "a big teddy bear ... who just wants to hug you," Martin said. "He's not one of the bad boys of the NBA that you hear about."

Judge Edward Coleman twice cut Martin off as he tried to tell the jury about Williams' abusive upbringing in Manhattan and again as he described Williams' trips to Christofi's grave.

Martin said Williams "is not, has not and will never be referred to as a mean person capable of taunting Mr. Christofi as the prosecutor wants you to believe."

He said Williams went out of his way to be kind to Christofi, paying for his meal and including him in the dinner discussion "because that's just how Jayson is."

"The working class guy is someone he appreciates," said Martin.

He said that when Williams grabbed Christofi — who stood only 5'6" to Williams 6'10" — it was to reassure him that they would take a picture later, not to threaten him.

He said the Globetrotters and other former associates of Williams who are testifying against him are simply trying to save their own skin and should not be believed. Martin largely glossed over the allegations of cover-up, saying the scene was chaotic and implying that some of Williams' friends might have suggested he mask the shooting as a suicide.

The jury of 12 women and four men, seated Tuesday morning after a month-long process, appeared to pay close attention to the opening statements. All are considered full jurors until immediately before deliberations when four alternates will be selected.

The final selection of jurors Tuesday morning was contentious, with defense lawyer Joseph Hayden accusing the prosecution of trying to exclude black jurors. Williams is the son of a black father and white mother. Although the prosecution did use six of its 12 peremptory challenges to remove panelists who were black, four members of the final panel are black women.

Judge Coleman scolded Hayden for playing to the "public arena" with his racism charge and noted that the percentage of black jurors — 25 percent — far exceeds the 7.5 percent of the county population that is black.

The trial is set to continue Wednesday morning with the testimony of state troopers summoned to the shooting.