Ryan Koss, age 35, agreed to a plea of negligent driving with death resulting.
He was given a one-year deferred sentence and will have his driving license revoked for a year.
He must also complete a community restorative justice program on the misdemeanor charge.
Treat WilliamsGregg DeGuire/WireImage/Getty Images
He failed to see Williams oncoming motorcycle, resulting in a collision.
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After the crash, Koss called Williams wife to tell her what happened.
Bennington County States Attorney Erica Marthage said Koss from the beginning has taken responsibility for the accident.
In the hearing on Friday, Koss apologized and offered condolences to Williams family and fans.
Im here to apologize and take responsibility for this tragic accident, he told the court.
Williams son Gill, 32, spoke directly to Koss, who he had met before the crash.
The family did not want to press charges or have Koss go to prison, he said.
I do forgive you, and I hope that you forgive yourself, he said.
But he also added that I really wish you hadnt killed my father.
I really had to say that.
Koss originally pleaded not guilty to a felony charge of gross negligent operation with death resulting.
Williams washonored last weekby his TV show, Blue Bloods.
He had a nearly 50-year career in more than 120 TV and film roles.
