Man convicted of involuntary manslaughter in death of Trooper Thomas Clardy

David K. Njuguna (left), State Trooper Thomas Clardy (right).
David K. Njuguna (left), State Trooper Thomas Clardy (right).Associated Press (left), State Police (right)

WORCESTER — A Superior Court judge on Tuesday convicted a driver of involuntary manslaughter in the 2016 crash that killed Trooper Thomas Clardy, but she acquitted the man of driving impaired on marijuana.

As Clardy’s family and dozens of state troopers looked on, Judge Janet Kenton-Walker delivered her verdict in the closely watched bench trial of David K. Njuguna, which became a flashpoint in the state’s 2016 debate over whether to legalize recreational marijuana.

Kenton-Walker found that Njuguna was speeding, tailgating, and weaving dangerously for about seven minutes before crashing into Clardy’s parked cruiser on the Massachusetts Turnpike in Charlton where Clardy had pulled over another driver. Rejecting Njuguna’s defense arguments that he suffered a medical episode before the crash, the judge also convicted Njuguna of misdemeanor motor vehicle homicide, driving to endanger the public, and driving an uninsured car.


“This was not an accident,” Kenton-Walker said. “Mr. Njuguna’s conduct was intentional. His conduct was wanton and reckless.”

But she cleared Njuguna, a medical marijuana patient, of two additional counts of manslaughter while driving under the influence of marijuana and felony motor vehicle homicide, finding that prosecutors didn’t prove he was too high to drive safely at the time of the crash.

Njuguna, 33, of Webster, was taken into custody after the verdict and faces up to 25 years behind bars. His sentencing is scheduled for Nov. 21.

Prosecutors alleged Njuguna was high on medical marijuana on March 16, 2016, when he lost control of his Nissan Maxima while speeding at 80 miles per hour and crashed into Clardy’s cruiser, killing the 44-year-old married father of seven from Hudson.

Officials said Clardy had returned to his vehicle after pulling over a driver for a traffic violation when the cruiser was struck by the Maxima, which did not slow down before impact.


Njuguna, who used marijuana to treat insomnia and severe leg pain, had purchased four prerolled cannabis joints at New England Treatment Access in Brookline about an hour before the crash, Kenton-Walker said.

The evidence showed Njuguna smoked a portion of a joint before the crash, Kenton-Walker said, but she said it would be “speculation” to conclude that Njuguna was too impaired to drive safely because of that.

“The fact that Mr. Njuguna consumed some marijuana prior to the crash does not prove that he was intoxicated or that his ability to operate was impaired,” Kenton-Walker said.

Njuguna had THC, the main psychoactive chemical in marijuana, in his blood about an hour after the crash, Kenton-Walker said, but that was not enough to prove impairment.

THC can remain in someone’s blood for days or weeks after cannabis consumption and its levels don’t correlate to someone’s level of impairment. There is no reliable scientific test to prove someone is too stoned to drive.

Governor Charlie Baker has filed a bill that would boost prosecutors’ abilities to convict people of drugged driving through the use of “drug-recognition experts,” specially trained police officers. But defense attorneys and civil liberties advocates say that approach is not scientifically reliable. Several Massachusetts judges have not allowed the officers to testify as experts in some court cases for that reason.

After Tuesday’s verdict, the State Police Association of Massachusetts urged passage of the bill, saying “As marijuana use increases in Massachusetts, we can expect to continue to see an increase in impaired driving as well.”


While Baker’s bill is needed, the verdict was not illustrative of every case, said John Scheft, a former Middlesex County prosecutor on the state’s special commission on operating under the influence. He said prosecutors regularly convict stoned drivers on evidence that they drove dangerously and had recently consumed marijuana.

Jim Borghesani, the spokesman for the pot legalization ballot campaign, said authorities always have been able to remove dangerous drivers from the roads, even if they couldn’t win convictions. He said people have been driving on cannabis “for decades,” but marijuana legalization drew attention to the need for a reliable test to measure impairment.

Two weeks before the 2016 cannabis vote, Clardy’s widow, Reisa, appeared in a video opposing legalization, saying, “You’re going to have families that are going to be without their loved ones.”

“My husband’s not here anymore,” she said then. “Daddy’s not going to come walking through that door one day.”

Colonel Kerry A. Gilpin, the outgoing State Police superintendent, said the verdict would not end the pain felt by everyone in Clardy’s life.

“There always will be an empty seat at the Clardys’ table, and hole in the hearts of the Massachusetts State Police,” Gilpin said. “This verdict cannot bring Trooper Clardy back to his family, friends, and colleagues, but it does provide some sense of justice by holding the defendant accountable for his actions that day.”

Njuguna’s friends said the case was tragic and they felt awful for Clardy’s family. “We lost a very good public servant and it’s hard for everybody involved,” said Christopher Cheonga. “Hopefully we can just find the peace to move on.”


Danny McDonald of Globe staff contributed to this report. Naomi Martin can be reached at naomi.martin@globe.com. Follow her on Twitter @NaomiMartin.