Someone blindfolded Doris Jiménez and bound her hands and feet. Someone left her in the back of her small clothing store with cuts and bruises on her body. Someone shoved a piece of cardboard down her throat. And someone strangled Jiménez, 25, until she was dead. "It is excruciating for me, knowing that her killers are still out there," says Eric Volz, 27, an American businessman who dated Doris for a year. "I want nothing more than for the real killers to be brought to justice."

According to Nicaraguan authorities, Volz need look no further than the cell he now occupies in the squalid Tipitapa prison near the capital of Managua, where he has just begun serving a 30-year sentence for killing Doris Jiménez. His arrest and trial have been a major story in Nicaragua, where Volz is largely seen as a rich, arrogant gringo who tried to get away with murder. But his friends and distraught family insist Volz is innocent and that his trial was a farce, with a judge tossing out evidence that seemed to prove Volz was some 90 miles away when Jiménez was killed. "We're used to seeing CSI, with expert autopsies and definitive evidence, but here it's still like the wild west," says Donn Wilson, a real estate developer in Nicaragua who knew Volz. "Nothing adds up."

Is Volz a callous killer or the victim of shoddy forensic work and anti-American fervor? It depends on whom you ask. An avid surfer and Latin American studies major at the University of California at San Diego, Volz moved to the coastal village of San Juan del Sur in 2005 to start a bilingual local-interest magazine, El Puente. "He could talk to everyone, from campesinos [farmers] to businessmen," says his friend David Brownlee, who, like Volz, worked with Century 21 in San Juan del Sur. In 2005 Volz met Jiménez, a waitress in a restaurant where he liked to eat. "She had a great presence," says his mother, Maggie Anthony, 56, an interior decorator. "They had really great chemistry."

His friends say Volz lent Jiménez money to open a boutique, Sol Fashion. "He supported her and wanted her to grow," says Jon Thompson, 32, who roomed with the couple for six months. "I never saw them fight. Eric was not the jealous or domineering type." But Jiménez's mother, Mercedes Alvarado, 45, says Volz actually owed Jiménez $1,700. "Eric is very jealous," Alvarado says her daughter told her. "He won't let me wear anything [revealing]." José Antonio Herrera, who worked next door to Sol Fashion, says, "Doris told me they were fighting because he wanted her to move to Managua with him and she didn't want to. She said she was scared of him."

Volz did move to Managua in 2006, and he and Jiménez "drifted apart," says Brownlee. "But there were no blowouts or anything crazy." Yet one of her friends, Ricardo Herrera, says that three days before the murder, he saw Volz get into an argument with Jiménez at a disco and watched him be restrained by Thompson from hitting her. Thompson calls that account "a lie."

On Nov. 21, 2006, police found Jiménez's body; within days Volz was the prime suspect. At his trial, Volz—charged along with two local vagrants, Nelson López and Julio Chamorro—said he had been in Managua, some two hours away, on the morning Jiménez was killed. The evidence included cell phone records placing Volz in Managua and showing he took part in a 12:19 p.m. conference call with two colleagues, as well as computer records that showed he instant-messaged one of the men during the call. Cell phone records also revealed a progression of calls from Managua to San Juan in the hours after Volz learned Jiménez had been killed.

And there was more: Ten witnesses claimed they saw Volz in Managua on Nov. 21. Only one—Nelson López, who had the charges against him dropped when he agreed to testify against Volz—says he saw him in San Juan. And tests showed blood found at the crime scene did not come from Volz. "Eric would call during the trial and say, 'It's going great, don't worry,'" says his mother.

But then, after three days, the judge, Ivett Toruño, issued her verdict: guilty. (Volz elected to be tried by a judge rather than a jury.) Toruño disregarded the testimony of the witnesses, saying it wasn't credible because they were all friends or colleagues. She brushed aside the cell phone records because they didn't prove Volz himself made the calls. DNA tests that could have shown the blood at the crime scene came from another suspect were, inexplicably, not performed. Instead the judge cited scratch marks on Volz's upper back as the main evidence against him. She claimed they could only have been made by Jiménez as she fought him off (tests on human matter found beneath her fingernails were inconclusive); Volz insisted the scratches were caused by her coffin, which he carried during her funeral.

Why, then, did Toruño seemingly throw out all the evidence that favored Volz? "Had she acquitted Eric, somebody would have been killed," says his father, Jan Eric Volz, a music tour manager, referring to the angry anti-Volz crowds that gathered near the courthouse. (Toruño could not be reached for comment.) Volz's side notes that Jiménez's mother, an organizer for Nicaragua's leftist Sandinista party, incited the crowds. Alvarado says she was only looking out for her daughter and claims someone connected to Volz's defense offered her $1 million to forget about the murder. "He said, 'Your daughter won't come back to life, so let's negotiate,'" she says. "I said I don't need 1 million, I need my daughter." Volz's parents deny making any offer and say the claim reflects the outrageousness of Alvarado's tactics.

Trial watchers believe Volz's icy demeanor during the trial didn't help his cause. Others doubt his alibi because it seems too carefully constructed. Volz now spends his days in a tiny cell with no running water. He has no theories about who killed Jiménez—even though his codefendant Julio Chamorro was also found guilty and sentenced to 30 years—but says, "I know I am innocent."

Back in Nashville his mother, father and stepfather have contacted two U.S. senators and are pressing the State Department to get involved. Far from being the rich fat cats the Nicaraguan press portrays them to be, "We're all broke," says Maggie Anthony, who, like Volz's father and stepfather, has gone through most of her life savings trying to free Volz. She has visited her son in prison, bringing him e-mails from supporters and briefing him on the case (his appeal will be heard by a three-judge panel, though no date has been set). "It's been a hard, hard fight, and I don't dare hope anymore," she says. "People say, 'This is your worst nightmare.' Well, this is beyond our worst nightmare. We're fighting for our son."