Skip to Content
Streetsblog New York City home
Streetsblog New York City home
Log In
Cy Vance

Man Who Killed Sister Mary Celine Graham in NYPD Chase Pleads to Murder

A man who plowed into a crowd of Harlem pedestrians while fleeing police, killing a nun, has pleaded guilty to murder.

Sister Mary Celine Graham

On the morning of June 22, 2010, police investigating a string of gunpoint robberies stopped a minivan occupied by Dyson Williams and William Robbins near W. 142nd Street and Adam Clayton Powell Boulevard, according to a press release from the office of Manhattan District Attorney Cy Vance. As officers questioned Robbins outside the vehicle, Williams, who was in the passenger seat, got behind the wheel and drove away.

Police reportedly pursued with lights and sirens. At W. 122nd Street and Lenox Avenue, Williams collided with another vehicle and careened into a group of people.

Four bystanders were injured. Sister Mary Celine Graham, 83, was killed.

Williams was charged with murder, along with a host of other charges related to the crash and the robberies. Today in state Supreme Court, he pleaded guilty to second degree murder, robbery and assault. Williams, 22, faces 18 years to life in prison. His sentencing is scheduled for May 30.

"Murder was not committed with a gun or a knife in this case, but a car," said Vance. "Before the deadly crash, the defendants in this case had embarked on terrifying gunpoint robbery spree in Harlem. Dyson showed an utter disregard for human life and his actions had tragic and deadly consequences."

Robbins was also charged with murder. Since he was not in the vehicle at the time of the crash, experts said the case against Robbins will test the boundaries of the state's felony murder statute. Robbins is next due in court on May 14, according to an online court database.

In the aftermath of the crash, NYPD Commissioner Ray Kelly said no departmental rules were broken. Kelly characterized the chase that preceded the collision as "appropriate police tactics."

The crash that killed Sister Mary Celine was one of a series of NYPD chases around that time that resulted in injury and death. Six months earlier, Karen Schmeer was fatally struck by men suspected of taking over-the-counter allergy medicine from a CVS pharmacy on the Upper West Side. In August 2009, restaurant worker and father of three Pablo Pasares was run over in Long Island City by a man after an alleged drug buy. According to witnesses, a suspected car thief was fleeing police when he hit and killed 38-year-old Greenpoint mother Violetta Kryzak in April 2009. In February 2009, a video camera captured an apparent Staten Island chase that led to the death of a couple with young sons. In June 2009, nine people, including five pedestrians, were injured when officers responding to a call in a marked NYPD squad car collided with another car and ended up on an East Village sidewalk.

Stay in touch

Sign up for our free newsletter

More from Streetsblog New York City

Streetsblog’s ‘Car-Free Carolers’ Bring the Joy, Mirth and Ho-Ho-Hope to this Holiday Season

Streetsblog's singers are back, belting out their parody classics to make a serious point: New York's roadways don't have to be dangerous places for kids and lungs, but can be joyous spaces for people to walk around, shop, eat or just ... hang out.

December 18, 2025

At Last: Council To Pass Delivery Worker Deactivation Protections

At its final full meeting, the Council is poised to deliver protections to delivery workers.

December 18, 2025

Serious Traffic Injuries Went Up This Summer Under Adams, Bucking a Trend

The city recorded a 5-percent increase in serious injuries in the most-recent quarter, though overall injuries are down.

December 18, 2025

Thursday’s Headlines: The Parks Mayor Edition

A coalition of greenspace-loving groups is demanding that Zohran Mamdani make good on his promise to raise the Parks Department's budget. Plus other news.

December 18, 2025

Mamdani Vows To Appeal Ruling that Killed DOT’s Astoria Bike Lane

The city has yet to appeal the nearly two-week-old ruling — but a new mayor says he'll change that pronto.

December 17, 2025

OPINION: I Led the Campaign To Get Cars Out Of Central Park, But I Strongly Oppose an E-Bike Ban

People now calling for a ban on e-bikes seem to forget what the park was like before cars were banned. It was way worse.

December 17, 2025
See all posts