“The visibility study and witness statements concluded that the cause of the crash was the blind spot in front of the tractor-trailer,” prosecutors said.

Investigators determined that “it was very likely that the driver of the truck could not perceive the cyclist as the cyclist entered the lane of the travel without signaling and based on the cyclist’s speed and location,” the Middlesex District Attorney’s office said in a statement.

The driver of a tractor-trailer involved in a bicycle crash that killed a 60-year-old man in Cambridge in 2016 will not face charges, prosecutors said Monday.

The crash happened just after 8 a.m. on Massachusetts Avenue in Porter Square. The cyclist, Bernard Lavins, 60, of Lexington, was struck in the middle southbound lane.


Investigators concluded that Lavins “exited the bike lane, which continues along Massachusetts Avenue to the intersection for Somerville Avenue, with the intention to turn left approximately 36 feet prior to the crosswalk,” prosecutors said.

“There is no indication that mechanical failure, conditions of the roadway or the roadway design contributed to this collision,” prosecutors said. “The operator of the truck was not speeding, impaired or distracted by cell phone or other objects at the time of the crash.”

The driver of the tractor-trailer remained at the scene after the crash, prosecutors said.

After the initial crash, the cyclist was struck by a second vehicle. That driver will also not be charged, prosecutors said.

In January, a bicycle advocacy group asserted that Boston police should not have cleared a truck driver involved in a fatal crash with a cyclist, saying video evidence shows the driver acted recklessly.

Maddie Kilgannon can be reached at maddie.kilgannon@globe.com. Follow her on Twitter @MaddieKilgannon.