Jeffrey Pyne Update: Murder trial begins for Mich. valedictorian accused of killing mentally ill mom

(CBS) Testimony began Friday for former high school valedictorian and University of Michigan student Jeffrey Pyne, accused of the beating and stabbing death of his mentally ill mother, The Detroit Free Press reports.

According to CBS Detroit, the 22-year-old Pyne is charged with first-degree murder in the death of his 51-year-old mother, Ruth, who investigators say had been beaten and stabbed 16 times in the neck. Her body was found by her young daughter in the garage of their Highland Township home, about 25 miles south of Flint, in May 2011.

The Free Press reports that Pyne's boss at Spicer's Orchard and Farm Market testified Friday the 22-year-old student had scrapes and blisters on both hands on the day of his mother's slaying.

During opening statements, prosecutors said that Pyne had become became angry with his mother and brutally killed her, while the defense contended that there was no evidence linking him to the slaying.

Prosecutors previously said testimony from family, friends and co-workers to a grand jury produced evidence linking Jeffrey Pyne to the crime.

The Free Press reports that Ruth Pyne had a history of mental illness, and was arrested in 2010 for allegedly attacking her son. She spent two weeks in jail for the incident.

Jeffrey Pyne's father, Bernard, told ABC News he believes his son is innocent. Ruth Pyne's siblings have also said they support their nephew, the Free Press reports.

The now 22-year-old suspect graduated first in his class at West Highland Christian Academy, a private school in Milford Township.

More on CrimesiderNovember 13, 2012 - Jeffrey Pyne, Mich. valedictorian accused of killing mentally ill mom, heads to trial