A MOM IS BRUTALLY MURDERED REVEALING SHOCKING FAMILY SECRETS - IS THE KILLER AT HOME? "48 HOURS: THE PERFECT FAMILY" SATURDAY, JAN. 12, 2013

Bernie Pyne returned home one day in May 2011 with his young daughter to find his wife Ruth in the garage, brutally beaten and stabbed to death.

The savage murder of the suburban mom was so shocking that even veteran detectives were stunned. Ruth Pyne was found in a pool of blood and beaten so badly her skull was cracked open. It was one of the worst crimes Detective Sergeant Greg Glover had ever seen in his nearly 25-year career, he tells 48 HOURS. "We knew that there was some type of rage," Glover says. "We felt it was something that was personal."

To outsiders, the Pynes appeared to be the all-American family. Bernie Pyne was a successful auto engineer who, with his wife, raised a seemingly happy family in a suburb of Detroit. They had two children, the oldest, Jeffrey, was his high school's valedictorian and on his way to college.

After Ruth was murdered, police would learn life inside wasn't so perfect. The investigation immediately turned to those who lived with Ruth, and along the way investigators learned Ruth had some psychiatric issues, including arguments and confrontations about her medications. Investigators learned Ruth and Bernie's marriage was fractured, and that Bernie had an affair. They also found Ruth's relationship with their son, Jeffrey, was also strained.

"Nobody knows what goes on behind closed doors and in someone's home. The family was not the family it appeared to be," Glover says on 48 HOURS: "The Perfect Family," to be broadcast Jan. 12, 2013 (10:00 PM ET/PT) on the CBS Television Network.

Ruth's sister Linda Jarvie thought Bernie was responsible for the murder. Given his affair, he understood the suspicions. "As a husband, to have your wife brutalized like this is the most painful and humiliating thing that can happen to a person," he tells Tracy Smith. "And then, to have people think that you could do it, is the most disgusting and debilitating thought you can have."

Five months into the investigation, Jeffrey Pyne was charged with his mother's murder. His attorney says he didn't do it. Police have no direct evidence tying him to the crime. Moreover, at trial, his attorney argues against a lesser charge of second-degree murder, rather than the original charge of first-degree murder, believing it would make it easier for a jury to convict him.

"The boy didn't do it," Bernie Pyne says. "My son would never harm his mother. They have this wrong. The police make mistakes and this is a mistake."

Tracy Smith and the 48 HOURS team report on Ruth Pyne's murder, the investigation and Jeffrey Pyne's trial through interviews with Ruth's sister, Bernie Pyne and investigators on the case. "The Perfect Family is produced by Liza Finley, Marc Goldbaum and Ruth Chenetz. Al Briganti is the executive editor. Susan Zirinsky is the senior executive producer.

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