By Daily Mail Reporter PUBLISHED: 23:02 EST, 11 September 2013 | UPDATED: 01:25 EST, 12 September 2013 A 19-year-old man and his 20-year-old pregnant wife have been charged in connection to the slaying of a state trooper who was shot dead during a routine traffic stop in northern Michigan. Trooper Paul Butterfield, 43, was shot in the head during in Mason County’s Sherman Township, about 80 miles north of Grand Rapids. Eric Knysz, of Luther, was charged Wednesday with murder of an officer as well as three other crimes. His wife, Sarah Knysz, faces two charges related to driving away from the scene with him.
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Eric Knysz, 19, charged with murder in shooting death of Michigan Trooper Paul
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Sarah Knysz, 20, charged as an accessory for leaving crime scene; she is currently six months pregnant
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Butterfield, 43, was airlifted to hospital but died in surgery after being shot in the head
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Mr Knysz has rap sheet dating back to his first offense committed at age 14
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Has been sentenced to 1,006 days behind bars since 2008, but served only 34
Spaniola said @placeholder regularly handled cases in Mason County, especially following up with sex offenders to ensure they were complying with their many restrictions.