Pomona Superior Court Judge George Genesta, who denied the defense's request for a new trial, also ordered Wesley Brockway to serve an additional two-year prison term.
The Ontario man was convicted Sept. 19 of attempted murder, battery with great bodily injury and aggravated mayhem, but acquitted of conspiracy and torture charges stemming from the Sept. 30, 2007, attack on the then-47-year-old victim outside his cabin on Mount Baldy.
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Deputy District Attorney Stefan Mrakich contended that Brockway attacked the man with a samurai sword with a three-foot-long blade because he was angry that the victim painted out graffiti he had left on a pavement trail leading to the cabin.
The victim's left arm was nearly severed, his pinkie finger was severed but re-attached and his shoulder was split in two, Mrakich said.
"He has limited movement of his left arm," the prosecutor said earlier, noting that the man has no use of his left pinkie.
Brockway's older brother, Eric, was convicted Sept. 19 of misdemeanor battery for using pepper spray after the victim had already been wounded with the sword, but jurors acquitted the now 34-year-old man of attempted murder, conspiracy, torture and aggravated mayhem.
The older sibling, who was not accused of using the sword, was charged under a "conspiracy and aiding and abetting theory," according to the prosecutor.
Eric Brockway was sentenced Sept. 19 to six months in county jail, which he had already served, and was released from jail shortly after the verdict.