(NASHUA, N.H.) -- A 21-year-old man who admitted killing a New Hampshire mother and stabbing her daughter in a random knife and machete attack was convicted of murder Friday. Jurors rejected his insanity claim, concluding he was sane on the night of the brutal attack.
The jury found Christopher Gribble guilty of first degree murder, attempted murder, conspiracy to commit murder, conspiracy to commit burglary and witness tampering.
Gribble stabbed Kimberly Cates to death and tried to kill her 11-year-old daughter in early October 2009. Gribble used a Boy Scout knife, while his convicted accomplice -- Steven Spader, already sentenced to life in prison -- used a machete in the attacks.
The husband and father of the victims, David Cates, spoke to the court Friday, thanking the prosecutors for their work. He addressed Gribble and called him a "worthless coward" for slaying a woman and attempting to kill her daughter, both of whom, he said, were helpless against his "gutless" attack.
Jaimie Cates, the surviving daughter who is now 12, left the room during her father's statement. She rejoined afterward to hear Gribble's sentencing.
Clad in an orange prison jumpsuit, Gribble appeared to have no reaction as the judge sentenced him to a lifetime behind bars.
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