Police officer charged with murder in killing of handcuffed man

Corporal Michael Owen Jr shot William Green seven times after arresting him for driving while intoxicated

Corporal Michael Owen Jr (Prince George's County Police Department)

A police officer accused of shooting dead a man who was already handcuffed and sat inside his patrol car has been charged with murder in the US state of Maryland.

Corporal Michael Owen Jr fired seven times at William Green while the pair were alone in the vehicle in Temple Hills, close to Washington DC, police say.

The officer had arrested the 43-year-old while responding to calls reporting that a driver had struck several cars and was intoxicated behind the wheel.

But it remains unclear why the veteran of 10 years then drew his gun as he and his partner awaited a drugs expert to take evidence from Green.

Speaking to journalists less than 24 hours after the incident, Prince George's County Police Department’s police chief Hank Stawinski said: “I am unable to come to come to our community this evening and provide you with a reasonable explanation for the events that occurred last night.

"I have concluded that what happened is a crime...There are no circumstances under which this outcome is acceptable."

He called the decision the "the most difficult moment of my tenure as your Chief of Police"

Rights groups have condemned the killing.

Cpl Owen and the unnamed partner had dispatched to Temple Hills just before 7.20pm local time on Monday evening.

The pair arrested Green, a father-of-two said to work for Megabus, and had placed him in the front passenger seat of their patrol car with his hands cuffed behind his back when the shooting occurred.

The officer was not wearing a body camera at the time. It is not clear if his partner witnessed the killing.

Cpl Owen was charged with second-degree murder, voluntary and involuntary manslaughter, first-degree assault and use of a firearm to commit a violent crime.

Deborah Jeon, legal director for the American Civil Liberties Union of Maryland, said: "There is no reason why a handcuffed person should ever be shot multiple times by a police officer, let alone shot multiple times inside a patrol car."