WORCESTER (CBS) – The driver in a Mass Pike crash that killed Massachusetts State Police Trooper Thomas Clardy was arraigned on charges of motor vehicle homicide and manslaughter.

In Worcester on Wednesday, 30-year-old David Njuguna of Webster appeared in court with braces on both of his arms. He pleaded not guilty to the charges after they were levied by secret indictment.

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The prosecution asked for Njuguna to be held without bail. Njuguna’s defense argued that he is not a flight risk.

Njuguna was ordered held on $500,000 cash bail.

Prosecutors said a burnt marijuana cigarette was found in Njuguna’s car and he had a level of THC in his blood.

“He absolutely denies that he was under the influence of any drugs,” Njuguna’s attorney Peter Ettenber said after his client appeared in court.

Troopers sealed off the scene after the crash. (WBZ-TV)

Troopers sealed off the scene after the crash. (WBZ-TV)

Prosecutors claimed during the arraignment that Njuguna was under the influence of marijuana at the time of the March 16 crash in Charlton.

Njuguna allegedly was in possession of four medical marijuana cigarettes. He had a card to legally carry medical marijuana.

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Clardy was killed when his cruiser was slammed into by Njuguna’s Nissan Maxima as the trooper made a traffic stop.

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“We do not have any evidence that this was an intentional act,” said Worcester District Attorney Joseph Early at a press conference following the arraignment.

Njuguna’s full list of charges includes manslaughter, manslaughter by motor vehicle, motor vehicle homicide by negligence, motor vehicle homicide while operating under the influence of drugs, negligent operation and operating an uninsured vehicle.

State Trooper Thomas Clardy. (Photo credit: Mass. State Police)

State Trooper Thomas Clardy. (Photo credit: Mass. State Police)

Prior to crashing into Clardy’s cruiser, Njuguna allegedly swerved across three lanes of traffic.

Njuguna had previously been served a summons on charges of negligent operation of a motor vehicle and failure to stay within marked lanes.

David Njuguna’s Attorney Speaks

The Webster resident had been hospitalized with injuries suffered in the crash. Family members told WBZ-TV following the incident that Njuguna claims he doesn’t remember anything from the crash.

Massachusetts State Police Col. Richard McKeon spoke following Njuguna’s arraignment.

“While we continue to heal as a police department, our healing will never be complete because in a perfect world, Tom should still be out there set up on his stretch of highway looking for dangerous drivers and keeping innocent motors safe,” McKeon said.

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Njuguna is next scheduled to appear in court on June 30 for a pre-trial conference.