KEY WITNESS IN MURDER CASE AGAINST ARIZONA STOCKBROKER SPEAKS OUT ON NETWORK TV FOR FIRST TIME IN "48 HOURS: END OF THE TRAIL"

"End of the Trail" Is First of Four Consecutive All-New "48 Hours" Broadcasts to Air Mondays at 10:00 PM, ET/PT

A key witness in the murder case against Arizona stockbroker Steven DeMocker speaks out on network television for the first time in an interview for "48 HOURS: End of The Trail" to be broadcast Monday, May 26 (10:00 PM, ET/PT) on the CBS Television Network.

DeMocker was accused of killing his ex-wife, Carol Kennedy, on July 2, 2008. As Correspondent Maureen Maher reports, Kennedy, a 53-year-old mother of two and educator, was brutally beaten in her home, which was located in a secluded area outside of Prescott, Ariz. She was found after police were alerted by her mother, who said she was on the phone with Kennedy when she screamed, "Oh no!" and the line went dead.

"The person who killed her knew her and was very upset with her," says Joseph Moura, a private investigator who examined the case for 48 HOURS. "There's no reason to whack her seven, eight times over the head with a club."

DeMocker told police he was a mile and a half away on a bike ride at the time of the murder, which Moura says immediately makes him a suspect. DeMocker denied having anything to do with his ex-wife's murder.

The police investigation turned up no physical evidence tying DeMocker to Kennedy's death. Indeed, there was DNA from another man found under Kennedy's fingernails. What police found, however, was an ex-husband struggling with a heavy financial burden, a marriage that fell apart because of DeMocker's philandering, and a relationship frayed by anger.

"I always had a sense they were deeply in love with each other and the marriage had become toxic," DeMocker's girlfriend, Renee Girard, tells 48 HOURS in her first television interview.

Police arrested DeMocker three months after the murder saying they had a strong circumstantial case. Among the evidence police found was DeMocker had used his home computer to search "how to kill someone and make it look like a suicide."

The case, however, was far from over. Legal maneuvers, court delays and the death of a judge would delay a resolution in the case for five years. And then, thanks to Girard, the case would go in a direction nobody expected when she revealed critical information about DeMocker's activities after Kennedy's death.

"He was very constantly gripped with fear, fear of being arrested," Girard tells 48 HOURS. "And he was obsessed with plans to flee, saying, 'I'm afraid I'm going to be arrested for a crime I didn't commit.'"

DeMocker's family, including his two daughters, says he's a loving father who wouldn't hurt anyone. Conversely, prosecutors believe he killed Kennedy to avoid paying alimony and to gain access to an estimated $750,000 life insurance payout.

Could Girard's new information free DeMocker? Or will it be the information investigators need to lock up the case? 48 HOURS is there when the jury decides his fate.

Maher and 48 HOURS piece together Kennedy's death and the case against DeMocker through interviews with Girard, defense attorneys, Kennedy's friends, DeMocker and his family. 48 HOURS: "End of The Trail" is produced by Sara Hulse, Asena Basak and Clare Friedland. Al Briganti is the executive editor. Susan Zirinsky is the senior executive producer.

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