A con artist with a penchant for lying to friends and loved ones about his medical career and military heroics could face the death penalty for the near-decapitation of his Beverly Hills girlfriend, Cathy Ann Carrasco-Zanini.

James Duane Grzeslo was so believable, one of his ex-wives tells L.A. Weekly, that she converted to Judaism for him — “He forced me to live a kosher lifestyle,” she says — but later learned he wasn't even Jewish.

That former wife, Wendy Bowen, an executive in the insurance underwriting industry, was married to Grzeslo until 2009. She says she believed her husband was a cardiothoracic surgeon at the neonatal intensive care unit at UCLA Medical Center.

Grzeslo actually was a registered nurse. State officials yanked his RN license shortly after his arrest for Carrasco-Zanini's 2011 murder. It's unknown where he worked, or whether he tricked any medical facilities into letting him perform surgery. UCLA failed to return calls from the Weekly.

On Oct. 26, 2011, the morning of Carrasco-Zanini's slaying, Grzeslo called his Beverly Hills anger-management counselor, Marty Brenner, and told him, “ 'Marty, I'd like to have a session with you. I think I did something wrong,' ” Brenner testified last week at the preliminary hearing in L.A. County Superior Court.

Grzeslo faces a murder charge, and possibly the death penalty, due to the special circumstance of lying in wait, according to state documents obtained by the Weekly.

Bowen says she and another of Grzeslo's ex-wives are praying he'll be put away for good. “There's no doubt in my mind that he did this,” Bowen says. “Finding out that he slit [his girlfriend's] throat, it's hard to describe how freaked out I was.”

Carrasco-Zanini, a private bookkeeper, was found by police lying in a pool of blood in her apartment at 123 N. Hamilton Drive. “Her head was almost cut off,” says deputy DA Amy Carter.

Her left hand was clutching a phone cord connected to a phone that had been unplugged. L.A. County deputy medical examiner Job Augustine testified that Carrasco-Zanini had slowly bled out.

Hearing the tragic testimony, Bowen says, “I've cried and been hysterical for the past two days.”

Bowen remembers how Grzeslo would mispronounce his own physician specialty as “cardiothorastic” yet she didn't question that he was a respected doctor. In the early years of their relationship, they lived in Castaic and “he was very good at taking care of me, protecting me.”

But during a background check the couple underwent in 2008 or 2007 as part of her effort to adopt his two preteen children, Bowen discovered that her ex-Marine husband was no doctor and had never served in Vietnam, despite bragging about receiving commendations for bravery there.

After Bowen filed for divorce, Grzeslo entered Beverly Hills social circles, where he allegedly continued his masquerade.

Carrasco-Zanini's best friend from high school, Janie Grauman, a clinical social worker with the Motion Picture & Television Fund, tells the Weekly that she loved to dance and was “the most loyal friend I ever had.” She voiced concerns about Grzeslo but says that her friend, who was divorced, “had her reasons” for being with him.

Two Beverly Hills detectives testified that Grzeslo told Grauman and her husband, Richard Booth, that he consulted on cardiothoracic surgery for premature babies at a hospital in Woodland Hills — but no longer performed surgery due to an arm injury. Prosecutor Carter told Judge James R. Dabney that when Booth, an “educated man,” asked Grzeslo about his medical schooling, he avoided details.

The day of Carrasco-Zanini's murder, in text messages to counselor Brenner, Grzeslo allegedly wrote: “Been extremely moody and attacking lately.” He agreed to meet Grzeslo that afternoon, the counselor testified, and Grzeslo “looked white as a ghost. Disassociated. Out of his body.”

Brenner said that Grzeslo told him, “I think I killed my girlfriend.”

Beverly Hills Police Department officer Douglas Trerise testified that, when he arrived at Brenner's office, he “handcuffed the defendant due to spontaneous statements like he 'thinks he cut his girlfriend's throat.' ”

Detectives rushed to Carrasco-Zanini's apartment and found her body drenched in blood, the walls smeared with it.

Although murder is rare in Beverly Hills, Carrasco-Zanini's slaying quickly passed from the news, and Grzeslo's alleged fakery as a surgeon remained known only to Bowen and a few others. His LinkedIn page touts another apparently phony career: that of “certified forensic fraud examiner” and expert trial witness formerly with the U.S. government. Tim Atchison, of the Texas–based Association of Certified Fraud Examiners, tells the Weekly that Grzeslo was “never a certified forensic fraud examiner.”

Thomas Grzeslo testified last week that his younger brother's con-artist behavior dates to the 1980s in Chicago, where James passed himself off to his first wife as a radio broadcast engineer and said he'd been cited for bravery in Vietnam.

Thomas Grzeslo said his brother once showed him a certificate signifying he was a radio broadcast station engineer. But, Thomas testified, “It [wasn't] real. … I've held the FCC license required for that particular job since 1974.”

Thomas, an electronics technician for United Airlines in the Chicago area, said his brother called him the morning of Carrasco-Zanini's murder and said, “I need help. I just killed somebody. … I just ruined the family name.”

Bowen also drew a picture of the man she never knew, telling the Weekly that they met in May 2001 through online dating site YouDate; a few months later, she left her life in Utah and moved to California.

But Grzeslo was violent, Bowen says: “He would punch holes through the wall and rip computer laptops.” Grzeslo told her things like “Never screw a Jew!” and “If you want to ask for police protection from me, it would probably be wise to.”

Today she describes him as an “abusive psychopath.” He wasn't violent toward his kids, she says, but sometimes left suicide notes around the house for them to find.

Grzeslo is being represented by public defender Pamela Jones, who did not return several calls from the Weekly.

The prosecutor presented a slew of witnesses, including BHPD Detective Daniel Chilson, who testified that Grzeslo told police that the couple had been having problems when Grzeslo went to Carrasco-Zanini's place on the morning of her death.

According to police testimony, Grzeslo claimed Carrasco-Zanini threw a vase, a framed picture of the couple and jewelry at him — then stood in his way and hit and scratched him when he tried to retrieve his toiletries. Chilson said detectives found his story not credible because they found “no obvious indication of a fight or struggle.”

Augustine, who conducted the autopsy, says Carrasco-Zanini had only “minimal defensive wounds” — two small cuts on her right hand, one on her left, and a small slice on her chin — indicating that she did not have a chance to fight off her attacker.

According to Detective David Dimond, a neighbor saw a middle-aged man with gray hair, glasses and a limp walking toward the back door of Carrasco-Zanini's unit at about 8 a.m. the day of the murder. (In court last week, Grzeslo walked with a limp.)

Detective Mark Schwartz painted a picture of a wildly jealous Grzeslo. He cited an incident described to him by Janie Grauman in which Grzeslo became furious while at a funeral for a friend of Carrasco-Zanini's. He saw her there speaking to the friend's son — and, according to Schwartz, Grzeslo suspected the son was flirting with Carrasco-Zanini at his own mother's funeral. The couple argued. That, Schwartz says, was the “final straw” in the relationship.

Rona Leuin tells the Weekly that her daughter and Carrasco-Zanini's son had been childhood friends at Horace Mann School in Beverly Hills.

Carrasco-Zanini, Leuin recalls, was dedicated to her boy: “She was a very good mom, and always showed up to back-to-school night. … She did a stellar job of raising him. She was a wonderful single mom and I think that's why I particularly felt bad” about her death.

Grauman agrees Carrasco-Zanini was a wonderful mother. The two friends had very different political views but trusted one another implicitly, and Carrasco-Zanini chose Grauman as her emergency contact. “Unfortunately,” Grauman says, “I got that call at 7 p.m.” the day her friend was killed.

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