A Boston police officer has been charged with manslaughter after prosecutors say he used unjustified deadly force during a March 11 shooting in Roxbury that left a Dorchester man dead.

Officer Nicholas O’Malley, 33, pleaded not guilty in Boston Municipal Court after authorities accused him of fatally shooting 39-year-old Stephenson King during a police response to a reported carjacking. Prosecutors say body camera footage contradicts O’Malley’s claim that officers were in danger.

The case is now moving forward in court, with officials, police leaders, and Boston Mayor Michelle Wu weighing in.

What happened in Roxbury

Boston police responded to a reported carjacking near Tremont Street around 9:45 p.m. on March 11 and later located a vehicle near Linwood Square, according to officials.

Court documents say O’Malley and another officer approached the vehicle with guns drawn and gave commands. At times, King showed his hands and partially opened his window, but did not exit or turn off the vehicle.

Prosecutors say O’Malley told King, “Bro, I’m gonna f***ing shoot you,” before briefly switching to a Taser.

Authorities say King attempted to flee, reversing into a police cruiser and then moving forward again. As the car moved forward, O’Malley fired three shots through the driver’s window.

Assistant District Attorney Ian Polumbaum said, “It appears that all three bullets struck Mr. King, and two of them were found lodged in his body, causing his death.”

Court records state King was unarmed.

Why prosecutors filed charges

Suffolk District Attorney Kevin Hayden said the decision to charge manslaughter followed a review of evidence.

“What we have here is the unlawful killing of another,” Hayden said. “The evidence, as revealed to us through the investigation, is clear, and so we were left with the decision to charge manslaughter in this matter.”

Prosecutors say body camera footage contradicts the officer’s account.

Polumbaum said King was “maneuvering and clearly trying to drive away, rather than run anyone over.”

Investigators also concluded O’Malley’s claim that King “tried to run us over” was not “factually true.”

Defense and police response

O’Malley’s attorney, Kenneth Anderson, said his client believed he needed to act to protect another officer.

He criticized the arrest, saying, “I don’t know if it’s because it’s an election year or not.”

Hayden rejected that argument.

“This has nothing to do with an election year,” Hayden said. “That has nothing to do with public opinion, has nothing to do with politics.”

Boston Police Patrolmen’s Association President Larry Calderone said, “No officer ever wants to take a life, ever wants to discharge their firearm.”

“But we carry that piece of equipment to keep you and your family safe, and we do a very good damn job at it,” he added.

What Boston leaders are saying

Boston Mayor Michelle Wu publicly praised prosecutors and police leadership following the charge.

“I am grateful to District Attorney Hayden and Commissioner Cox for the urgency they have brought to this investigation and for their commitment to transparency in the pursuit of justice,” Wu said.

Boston Police Commissioner Michael Cox called the situation a “difficult day” and said the department would not comment further while the case proceeds.

What happens next

A judge released O’Malley on personal recognizance and ordered him to surrender any firearms. The case is expected to be presented to a grand jury.

Prosecutors said they will not release body camera footage during the ongoing case.

“To do so would clearly compromise and imperil the ongoing investigation and the future prosecution of this most serious matter,” Hayden said.

Why this matters in Massachusetts

Charging a police officer with manslaughter for an on-duty shooting is rare in Massachusetts, making this case a major test of how prosecutors handle use-of-force cases in Boston.

It also raises questions about transparency, public trust, and how police respond to rapidly evolving situations.

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FAQ

What is the Boston police officer charged with?
Nicholas O’Malley is charged with manslaughter in connection with the fatal shooting of Stephenson King in Roxbury.

Was Stephenson King armed?
Prosecutors say King was unarmed and had no weapons inside the vehicle.

Why did the officer say he fired?
O’Malley told investigators he believed the vehicle was about to strike another officer.

What evidence do prosecutors cite?
They say body camera footage and witness accounts contradict the claim that officers were in danger.

Will body camera footage be released?
No. Prosecutors said releasing evidence now could compromise the case.