The family of a developmentally disabled man who was brutally attacked for no apparent reason told his assailant in a Santa Rosa courtroom Thursday that the incident has left him despondent.

"You ripped away the loving, trusting, special person that he was," Kim Ridge, Austin Ridge's mother, said in a statement read Thursday during sentencing for Logan Dunning.

Judge Dana Simonds sentenced Dunning to 10 years in prison for attempted murder causing great bodily injury. The Boyes Hot Springs man pleaded no contest to the charge in September.

Austin Ridge is a beloved figure in Sonoma, where the 29-year-old was known for riding his trike for miles around the city every day, meeting people along the way. He became disabled in a car crash about a decade ago.

His family Thursday said the vicious and unprovoked attack worsened Ridge's physical injuries and caused lasting emotional scars. Ridge was riding home from a pub on April 25, 2012, when Dunning pounced on him, police say. Ridge was found on the side of the road with a broken jaw, stab wounds and other serious injuries.

"You are not a human being. You are a monster," Kim Ridge told Dunning, who sat in the jury box. "The years you spend in prison are not long enough and we will never forgive you."

Ridge's sister and grandmother also had statements read to the court. Austin Ridge was not present.

Dunning listened with apparent interest but he said nothing prior to being sentenced. The family said he had sent them a letter blaming Austin for the attack.

"He said it was Austin's knife and that's why he got stabbed," Kim Ridge said.

Dunning, who originally was charged with four felonies including mayhem, was preparing for trial when he agreed to a plea bargain. He faced an additional six counts of arson for a series of Santa Rosa car fires that occurred around the same time.

Simonds ordered Dunning to register as an arsonist as part of his sentence. She told him that he stands at a crossroads of being a "monster" who spends the rest of his life in prison, or a law-abiding citizen.

You can reach Staff Writer Derek Moore at 521-5336 or On Twitter @deadlinederek.

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