Smoke seeped from the eaves of the house and into the predawn darkness in a blue-collar Fort Stockton neighborhood in West Texas. The picture window looking out onto the street was aglow; the living room inside, a furnace, chugging smoke through a hole in the ceiling. It gathered in the attic and pressed down into the northwest bedroom and the office. Tar-black smoke and shimmering heat rolled across the living room ceiling and banked down the walls, spreading outward, blistering paint in the bathroom, melting plastic utensils in the kitchen.

Dois Clawson, a neighbor, heard pounding on her door at around 6:15. She peered warily out the window and saw no one, so she returned to bed. In the early morning quiet, though, there was "a commotion" next door. Clawson looked out through the window again and saw her neighbor, Sonia Cacy, wearing only a short, nylon nightie against the chill fall air, tracing frantic circles in her front yard. She hurried over to Cacy and asked what was wrong.

Her house was on fire, Cacy said, and she believed her uncle, Bill Roscoe Richardson, was still inside. Clawson saw the flames now through the window. She asked Cacy if she had called the fire department. She said she hadn't.

Cacy's front door was locked, so Clawson hurried back inside to call 911. Cacy stayed near her home and scanned for signs of her uncle in the thickening murk through the glass. When Clawson returned, she saw Cacy, a pretty 44-year-old with wide-set green eyes, just a shade over 5 feet tall, punching through the panes of the picture window with her small fists. Clawson gripped her arm and pulled her back, fearing the holes in the window would feed the flames.

She asked Cacy how she'd escaped.

Through her bedroom window, she replied.

They circled around to the far side of the house. Cacy leaned in through the window and pulled back, coughing. There was no air inside, she said. It was too hot. It was dark out, but Clawson would later testify that she didn't see smoke. As they returned to the front yard, Fort Stockton police officer Robert Curtis arrived. Cacy was screaming, "My uncle's in the house!"

Curtis kicked the door in and smoke poured out. He could see tongues of orange fire lashing through black, boiling clouds. He got on his belly and crawled through the door. Before he was halfway in, he said he felt "a pressure, pushing me down." Cacy was clambering over him to get inside. The officer wrapped her up, hauled her out of the doorway and told Clawson to hold her back. Cacy wrenched free and dashed toward the door again. "She was scratching, trying to get back into the house and, like I said, she was highly emotional, crying, and just struggling and trying to break loose," he testified.

"We took her over to [my] house and she calmed down for just a few minutes," Clawson said. "And then she wanted to go back outside because she said they weren't going to get Uncle Bill. And I got her a house dress ... to cover her pajamas."

Two other officers arrived and asked Cacy where Richardson might be. She said she thought he was in the living room. Officer Rick Carreon, who had been to the house on another fire call just over a week before, found a garden hose and pointed its weak stream at the flames. Another officer, Armando Villesca, crawled through the door, the beam of his flashlight penetrating only a few feet through the dense smoke. He found Richardson off to the left, near the corner of the living room. His body was so badly burned that it had the plastic, featureless appearance, he said, of a "mannequin." The officers decided to leave him inside.

"I didn't think there was anything we could do," Villesca later testified. "So we moved out, pulled ourselves out."

The officers were nauseated from smoke inhalation, retching dryly in the yard. Clawson's arms held a struggling Cacy in a bear hug, but could not keep her back. Cacy charged the house and was tackled by the officers again. She begged them to help her pull Uncle Bill out of the fire. Until the authorities finally took her to Pecos County Memorial Hospital, Cacy fought them, cursed them, even punched victim services coordinator Betsy Spencer in the gut.

On the ride to the hospital, soot staining the skin beneath her nose and around her mouth, blackening the front of the red house dress Clawson had given her, Cacy recounted the morning. What she wasn't sure about, Clawson said, was how she woke up. "She first told me Uncle Bill woke her up and told her to get out, and then later she told me she wasn't sure whether she had imagined that ... or if it had actually happened."

She asked Clawson if she thought Uncle Bill was dead. Clawson told her she believed he was. "She said, 'Are you sure he didn't get out?' And I said yes ... like she could not comprehend that actually he had died."

They checked her in at the hospital. The doctor noted singeing on her hair and some small cuts on one hand and on her legs. She was coughing up a "black-tinged sputum," and was suffering from bouts of vomiting brought on, the doctor reasoned, by stress and trauma. Her best friend, Loretta Scott, a schoolteacher, arrived not long after. "She was crying and incoherent, pretty much." Cacy kept asking about Uncle Bill. Had she heard anything?

For a patient in her state, it wouldn't be uncommon for the doctor to prescribe something to calm her down. But on the way to the hospital, Officer Carreon had raised Spencer on her two-way radio. On that day, November 10, 1991, he wanted her to relay to the hospital staff: "Do not sedate her."

At 4 that afternoon investigators walked through the house, reading the story of fire on the walls and following it back to the place where it started. Bill Richardson's body still lay on the soggy, soot-blackened carpet. Fort Stockton Fire Marshal Frank Salvato called in a representative from the state fire marshal's office, as well as Steve Kenley, fire marshal in Ozona, a hamlet of 3,000 or so an hour and half east of Fort Stockton.

They began at the outer reaches of the fire's destruction in bedrooms dusted with soot, searching for signs like trackers reading a game trail. They traced the smoke line as it descended lower and lower into the living room, where the fire was contained. A plastic clock was fused to the wall. In the corner, a television had melted. Salvato noted a web of fine cracks in the picture window, known as "glass crazing," which he attributed to the presence of an accelerant. Kenley eyed the charring to rafters spanning the hole in the ceiling, where the heat and smoke had been drawn into the attic. Richardson lay below, his clothes consumed by the fire but for the waistband of his pants and a few shreds of underwear. The skin on his legs was gone. Nearby were the remains of a collapsed aluminum cot. The investigators remarked on the pattern beneath it, burned into the carpet and deep into its padding. They believed they had found the area of origin. By the end of that day, Salvato had arrived at a conclusion.

"Noting area burn patterns; glass crazing, smoke travel, position of victim, statements from police officers, firemen, neighbors and Ms. Cacy, and two suspicious fires in the same house one week prior made this investigator to determine this fire to be arson," he wrote.

Word of the fire traveled quickly among Fort Stockton's 8,500 residents. It was a cowtown and rail depot until a massive Permian oil deposit was discovered in 1926. The fortunes of the town rose and fell with the price of a barrel ever since. Richardson was an oilman himself, but of the least prosperous kind; he operated a few stripper wells he bought from an oil company that figured they were too played out to fool with. Cacy had lived with or near him for most of her life and had recently returned to Fort Stockton after caring for her injured son and ailing husband, whom she was separated from. She considered Richardson a father and called him "Papa," and he had loved her like a daughter.

Now, she settled in to the reality of his death in a hospital room while Clawson daubed the soot from her face with a washcloth. Victim services coordinator Spencer recalled her saying repeatedly, "I don't think I can live long without my Uncle Bill."

It was at this moment that Officer Carreon stepped into the room and asked for a statement and a blood sample. Cacy was furious, and it was clear she blamed the police for failing to rescue Richardson. "None of this would have happened if the police had done what they were supposed to do in the beginning," she had said, according to testimony from Spencer. Cacy wouldn't give Carreon "a fucking thing," she spat, until she had spoken with an attorney. Within an hour or so, though, her friend had calmed her down. She went out into the lobby and informed the officer that Cacy was ready.

"And when I walked up and said this, the policeman was rather belligerent and said, 'You're right, she's going to give ... because we're going to subpoena her,'" Scott recalled.

Cacy wrote this terse statement, which she was assured she could later expand on: "My uncle woke me, I can't remember if he shook me, or what. I couldn't see or breathe. I went out a window. I knocked on the neighbor's door. She held me. I tried to go back. That's all I can remember."

That evening, a group of police and fire investigators filed into her room. Carreon handed her a warrant authorizing him to retrieve a blood sample and fingernail scrapings. Cacy quietly complied, and they left. The blood sample would test negative for the presence of drugs or alcohol.

Cacy had become the only suspect in an investigation that found what it believed was clear evidence of arson. As they combed the house, they found Richardson's handwritten will naming her the sole beneficiary of his estate.

They noted two suspicious fires at the residence just more than a week before, which occurred within hours of each other. Salvato connected the dots. The fire department hadn't been out to Richardson's house until after Cacy returned from caring for her husband and son.

A report came back from the medical examiner in San Antonio, concluding Richardson had died of "thermal burns" over 95 percent of his body, not from smoke inhalation and carbon monoxide poisoning. This fit perfectly with the story Kenley divined from the ashes of the living room. Much of the heat from the burning furniture around the body had escaped through the hole in the ceiling, so what was the source of the well-documented heat damage throughout the room? And where had it gone? By the time firefighters arrived, the blaze had been tamped down with a mere garden hose. "How can you have this searing heat and then have it diminish?" he wrote. "There is only one answer for this. Something burned very hot and very fast in this room. So hot and so fast that the vent was unable to handle it. Then, whatever it was burned up."

In the deep burn patterns beneath the melted cot, he saw the signature of just such a hot, fast fire. This was consonant, he believed, with the pouring of an accelerant. Paired with the report from a Bexar County lab that indicated the presence of something like gasoline in cloth remnants from the body, Kenley suspected the fire on Young Street was murder.

Meanwhile, Cacy sorted through the ruined furniture in the living room. The family portraits, photo albums and baby pictures that had enjoyed an altar-like corner on the bookcase, near where Richardson was found, had been destroyed. She washed her sooty clothes again and again, adding lemon juice and baking soda. But the smell of the fire clung stubbornly, and she had no choice but to throw them out.

The funeral home took what cash Richardson had in his bank account for burial expenses. It didn't cover the tab, so Cacy paid the balance and buried him in an inexpensive, cloth-lined casket. She wished she could have done something more, but was comforted in the knowledge that Richardson had never been a man known for style or extravagances. Her home uninhabitable, she moved in with her estranged husband in Fort Worth.

On April 16, 1992, some five months after the fire, Cacy was indicted for the murder of her uncle.

Inside the buff sandstone of the Pecos County courthouse, a clean-cut district attorney in his mid-30s made a promise to the jury on February 23, 1993. "You'll hear testimony that on November the 10th, 1991, this defendant smelled highly of alcohol. She reeked of liquor. You'll hear testimony that she was uncooperative with the police officers, cussing them, even punching one of them."

By the end of week, Albert Valadez continued, "I believe each and every one of you will be convinced beyond a reasonable doubt that this defendant, Sonia Cacy, caused the death of Bill Richardson by setting him on fire."

Over the course of several days, Valadez called to the stand Dois Clawson, the officers at the scene and the local fire marshal. He called Charles Bux, a pathologist from Bexar County, who testified to Richardson's grievous burns and to his agonizing death by fire. Valadez brought out Richardson's will, recovered from the bureau in Cacy's room, bequeathing his estate to her. And Steve Kenley, the fire investigator from Ozona, held the jury's rapt attention as he discussed the burn patterns, the charring of the rafters above Richardson's body, the soot on Cacy's clothes and face, and the singeing of her hair.

"If you've ever started a fire with gasoline or any type of flammable stuff ... and when you light it, you'll notice you have a little fireball," he said. "Well, that rises. It rises up to the point that it'll hit the ceiling of the house, then it'll have the tendency to — to come back."

"And might that gasoline from the ceiling cause her hair to singe?" Valadez asked.

"It could."

But the most damaging testimony came from Bexar County toxicologist Joe Castorena, who told the jury that the clothing remnants analyzed by his lab were positive for traces of a Class II accelerant, like gasoline. Tests performed by a Dallas lab on carpet samples beneath the cot and the body were negative for accelerants. Kenley explained it away by telling the jury that all traces of it most likely burned up.

Cacy's court-appointed attorney, Tony Chavez, presented a meager defense. He called as witnesses Cacy's son, Blake; Loretta Scott; a firefighter from Odessa with no training in arson investigation; and a beautician who burned some hair by holding it above a cigarette lighter to prove that it could singe without coming into contact with the flame. He hired no expert witnesses to challenge the medical and scientific testimony presented by the prosecution. About the finding of an accelerant, he said during his closing argument: "I have no quarrel with that. I have no quarrel with that."

At the end of the five-day proceedings, the jury returned after two hours with a guilty verdict, and sentenced Cacy to 55 years in prison. Bailiffs drew their pistols, Cacy remembered, as her husband and son leapt to their feet. Blake chased her down the hall outside the courtroom as she was led away, bound for a prison in Gatesville. And were it not for chance, and the random intersection of two distant lives, her story, and the stories of others that had been irrevocably altered by fire, might have ended there. But in Fort Stockton, a town at the center of the great wide nothing of far West Texas, a statewide revolution in arson investigation was about to begin.

For nearly three years Cacy watched the world pass her by through chain-link fence and razor wire. Grandchildren were born. Milestones were celebrated. All the while, she retreated further inside of herself, the matriarch of the Cacy clan now a listless "zombie," as her daughter-in-law described her. When her 12-year-old granddaughter visited, the girl wept in confusion, asking her mother why Cacy could not come home with them. She kept the walls of her cell bare, knowing she would not be able to get out of bed in the morning to clerk for the prison substance-abuse counselors if she was greeted by the sight of all she had lost.

In 1995, however, a state appeals court remanded her sentence for a new punishment hearing. The district attorney, it ruled, had made inappropriate statements to the jury about Cacy's decision not to testify. She was released three months before the hearing scheduled for spring 1996. A Granbury attorney named Andrew Ottoway would represent her. Through a friend of his, he enlisted the assistance of an investigator from Austin named Gerald Hurst.

A towering, rangy man with a long gray beard and curiously intense eyes, Hurst had an apostolic, Old Testament effect. The son of divorced parents — a sharecropper in Oklahoma and a waitress in Los Angeles — he grew up splitting his time between the prairie and Skid Row during the Great Depression. He was a precocious kid who wandered the streets, sifting through junkyards for scrap he might use to build various gadgetry. As the counterculture of the '60s took root, Hurst received his doctoral degree from Cambridge. But he didn't join the movement. He developed high-explosive nose cones on napalm bombs to more effectively distribute their payloads in the jungles of Vietnam. He synthesized rocket propellant for Harshaw Chemical. He specialized in the applied science of covert warfare, tunnel destruction and classified weaponry designed to "burn things down behind enemy lines."

Hurst eventually tired of this work. "I was using my talents to destroy things," he said. He quit and joined a businessman who bankrolled his invention of the Kinepak, a commercial binary explosive whose constituents don't become hazardous until mixed. The business was bought out and consolidated with Atlas Powder. Hurst was named chief scientist and given the run of a 140-acre campus and lab in Austin. He negotiated himself a sweetheart deal, working just 10 hours a week on lab business, free to devote the rest of his time to whatever he chose. For nearly a quarter century, Hurst consulted on big-dollar civil cases that pitted top experts like him against one another in pitched intellectual battles.

That all came to a halt when his liver began to fail, due in large part, he suspected, to a career as an industrial chemist. His own doctor had given him up for dead, ruling out the possibility of a transplant at his age. Hurst fired the physician and found one at Baylor University Medical Center in Dallas who would place him on the transplant list. After near-fatal bouts with pneumonia and esophageal bleeding, he received a new liver in 1994. His odds of living beyond five years were slim.

In spring 1996, a fascinating case was dropped in his lap. He'd never testified at an arson trial before, but he was a chemist, and what was fire if not a chemical reaction? He talked his son Eric Rabbanian, a recent law school grad who'd only just passed the bar, into assisting him with the case. Rabbanian agreed, if only because he feared it would be the last case Hurst would ever take. Cacy and her husband, Billy, showed up at the doorstep of his airy Hill Country home carrying a box stuffed with transcripts and exhibits. Cacy was intimidated by this imposing figure, who listened impassively as she laid out her case, probing with the occasional question. Hurst, on the other hand, was charmed.

"He likes the damsels in distress," his wife, Gay, said with a chuckle.

He was still reading the trial transcripts as he and Rabbanian left the Hill Country and passed into the desert of the Trans-Pecos. "It was the worst work I'd ever seen," he said of the expert testimony. "I was used to working with scientists and engineers, and then I came face to face with fire investigators and I was just appalled."

Yet he began his investigation by looking for a motive: He needed to understand the relationship that had existed between Cacy and Richardson and to determine whether it was possible that she had in fact murdered him.

He learned, for instance, that she called him "Daddy" until she found out it hurt her father's feelings. Richardson's home was a refuge, a safe place for her to run when her alcoholic parents feuded. She spent much of her childhood within shouting distance of him. The family would gather on the porch, Cacy's father playing the fiddle and Richardson picking on his steel guitar. She saw less of him after her parents moved to San Saba when she was a teen, a little over a hundred miles northwest of Austin. But she always returned to Fort Stockton to visit.

She dropped out of high school as a senior, pregnant with a son, and married the child's father. The relationship didn't last. Pregnant with their second son, she divorced him and then left San Saba for Benbrook, southwest of Fort Worth. Her next-door neighbor, a man named Billy Cacy, never forgot the day she moved in. She looked like a pixie, with sandy hair she wore short and curly, a delicate figure and big green eyes. He wanted to marry her the moment he saw her. "She was a good-looking girl and she had two babies and she was a hard-working girl."

They married six months later, in 1967. Billy adopted her two boys, and they moved back to West Texas to be near her family. They lived in some desolate country near the Pecos River, in a shack without running water, housing her parents and Richardson as well. Her uncle and her father had purchased the rights to some aging oil wells that were near the end of their productive lives. Richardson taught Billy how to roughneck.

Cacy kept the books and filed the paperwork. Oil was going for around $3 to $4 a barrel. The wells weren't worth an oil company's time, but they pumped enough to keep food on the table. They took every meal together, and passed the evenings playing dominoes and listening to Richardson and Cacy's father make music.

Between 1972 and 1978, the price of oil quintupled. They weren't rich by any stretch, but times were better than they had ever been. Cacy's father bought her a house in nearby Imperial for $800, then he sold his stake in the oil lease and bought a house in Ruidoso, New Mexico. In 1980, he hit a patch of gravel on his way back to Texas and was killed in the crash. Richardson drove five hours to New Mexico, loaded Cacy's mother's things into his pickup, and brought her home. "My mom was just destroyed," she recalled. "She was gonna live up there all alone, and he went and got her and it made her happy."

Uncle Bill had always loved Cacy's mother, Zalie, like a sister, but Cacy knew he felt something more than that. He was a lifelong bachelor, but he married her the following year at age 66.

They moved back to Fort Stockton, and for a few years Richardson was happier than he had ever been. But Zalie's health was poor. And after only five years of marriage, she died. He'd lost his brother and now his wife. Cacy worried for him. He'd become depressed, suicidal. Cacy and Billy had divorced by then, so she and her daughter Gina moved in with Richardson. She took care of the lonely man and brought him to life again. She cooked and cleaned for him. He napped during the day and worked through the night in his shed, welding and fabricating oil-slickened equipment from his wells. He wore grease-soiled clothes roustabouts aptly referred to as "greasers" around the house, often sleeping in them.

If Richardson was rough-hewn, his house was worse. A hail storm had severely damaged the roof, and when it rained, water runneled onto the living room carpet. Instead of repairing it, they removed the ceiling board and placed a trash bin underneath.

They got by. Richardson sold a little oil. Cacy managed a motel. Sometimes she drank to excess, when the financial and emotional strain of raising a daughter and son with an absentee father became too great. She suffered a breakdown and had to be hospitalized for several weeks. She could lean on Richardson, though, and he on her. "He was always around. He's always been around," Cacy's son Blake said. "They were just best friends."

Hurst could not reconcile the official story with what he had learned. He couldn't envision Cacy murdering her uncle, much less for the nearly destitute man's worthless estate. The house wasn't insured, and the price of oil had fallen. Richardson was thinking about shutting his wells down. Where was the motive?

He was beginning to see another likelihood emerge. Richardson smoked two to three packs of cigarettes a day. His bed sheets, his clothing, the furniture all had cigarette burns. When he lost one between the cushions, he'd douse it with the nearest cup of coffee. Out in the oilfield, fire was a constant. When things went missing out on the lease, he taught Cacy's sons to look for the nearest pile of dead mesquite limbs and to set fire to it. It was a pack rat den that would likely contain what they'd lost. He taught them to light cooking fires from the venting natural gas of plugged oil wells.

Every member of that family had seen him roasting marshmallows and cocktail weenies with a propane torch while relaxing in his recliner. Small fires in wastebaskets into which he tapped his cigarette ash were common. He burned his credit card receipts in plastic pans inside the house. One freezing day in his cabin at the oil lease, he stuck a can of aerosol paint inside a gas space heater to thaw out. He must have forgotten about it, because it exploded as he warmed his backside, searing his skin from calf to scalp with boiling paint.

That there were two fires reported within hours of each other at Richardson's house the week before he died did not surprise those who knew him. The fatal fire was foreseeable. This history alone isn't what convinced Hurst. As he and Ken Gibson, a former Arlington fire investigator, walked the ruin of Richardson's house some four years later, the early November morning in 1991 came into focus. They found a piece of polyurethane foam mattress near where the cot had been, took it outside and held a lighter to it. The foam burned furiously and was transformed into a scalding liquid. It could easily account for the burn patterns in the carpet. In the 1998 issue of National Fire Protection Agency Journal, an article referred to the material as "solid gasoline," a "deadly and pervasive peril." It discussed whether the petroleum product should be banned. There were two polyurethane foam mattresses on the cot that morning, along with a polyester blanket.

The more intense charring above Richardson's supposedly flaming body, which Kenley identified in crime scene photos, wasn't what it seemed. Gibson, who has since died, stuck the point of his pocket knife into the char on the rafters and found it evenly distributed.

As for Cacy soaking a sleeping Richardson head to foot in gasoline, Gibson and Hurst couldn't see it. The stuff evaporates quickly, suffusing the air with flammable vapors. They couldn't envision a scenario in which her nylon nightie didn't instantly fuse to her body, causing severe burns. And the fireball that Kenley suggested may have bounced off of the ceiling and singed her hair? The investigators could only shake their heads in disbelief. This fire didn't need gasoline to ignite.

None of it fit the prosecution's narrative. In crime scene photos of the kitchen, they saw toast in the toaster. The autopsy indicated he was wearing his dentures, which he only wore when he ate or had company. All signs pointed to Richardson being up and about, making breakfast. But what to make of the pathologist's conclusions that he died of thermal burns? The autopsy report also mentioned that the descending artery in his heart was 80 percent occluded. His lungs were congested with a "bright-red, frothy fluid." There was soot in his mouth and in his nostrils, but none in his trachea or lungs.

The most troubling revelation, however, didn't come until the first day of Cacy's new sentencing hearing. Inside the Fort Stockton Police Department, Hurst reviewed the physical evidence. An unlined gallon paint can was handed to him. "I popped the can in the evidence room and looked into it and it was one of those Jesus moments," Hurst said.

It contained shreds of Richardson's underwear that had been analyzed by a Dallas lab specializing in such testing. It found no accelerant. No one had seen this evidence before. In the last trial, a Mason jar was submitted as the sole container of Richardson's clothing remnants, and was characterized as positive for gasoline. The paint can, toxicologist Castorena had testified, contained only some nondescript "other stuff." What's more, the can was signed and dated by the medical examiner. The jar was not, causing Hurst to question where it had come from. Why had this been kept from Cacy's attorney?

The same day, Hurst was given the test results Castorena relied on for his finding of the presence of an accelerant. Cacy's last attorney had never actually looked at them. Hurst had performed these kinds of tests before, using the same instrumentation. He wasn't seeing what Castorena saw. To get a second opinion, he showed the analysis to the same Dallas lab. The chemist told him that it certainly contained a number of byproducts from burning household items, but he did not detect the presence of gasoline either.

Hurst was stunned. Every single item from the scene was negative for accelerants. As the Fort Stockton fire marshal had testified at trial, the only accidental cause he had never been able to rule out was a cigarette. Hurst, Gibson and Cacy's attorney laid this all out for the jury during the new punishment hearing. The prosecution hammered away at what it characterized as Cacy's shifting story, reminding the jury repeatedly that she'd already been found guilty.

As the jury prepared to deliver her new sentence, Cacy squeezed Rabbanian's hand. The number they heard knocked the wind out of them. "I came in with 55 [years] and now I have 99," Rabbanian remembered Cacy saying. After everything the jury had learned, he couldn't understand how it had reached this conclusion. The young lawyer would never touch another criminal case.

Hurst couldn't let it go. He sent the test results to Dr. Richard Henderson, an expert in chemical analysis who often lectured at the FBI National Academy. He too agreed that they should be read as an unequivocal "none detected" for gasoline. He sent the autopsy report to the director of the forensic pathology division at the University of Miami School of Medicine, and to the deputy medical examiner for Cook County, Illinois, as well as a few others. Each concluded independently that Richardson had died of a heart attack, not thermal burns.

Cacy's case began gaining attention in the national media. The Wall Street Journal and Dateline NBC performed extensive investigations of her case at Hurst's urging, going as far as hiring their own experts to review the evidence. They reached the same conclusions. In 1998, Hurst and Rabbanian presented her case to the Board of Pardons and Paroles. It was the longest of long shots. The board never granted parole to a convicted murderer serving a life sentence, who refused to express remorse for her crime, or to even admit it at all. But the board was so moved by the evidence that it released Cacy six years in to a 99-year sentence.

She walked out of prison November 23, 1998, at the age of 51, still guilty in the eyes of the state but free. The prison parking lot was filled with well-wishers like Gerald Hurst and Rabbanian, and with TV news crews, newspaper reporters, all there for Cacy, a woman raised in the remote oil fields, but whose name was now synonymous with bad science and miscarried justice. "I want my name cleared," she told the San Antonio Express-News that day. "I want to be found innocent."

A murder conviction was a stain that wouldn't wash, Cacy learned on the outside. Finding decent housing was hard when nearly every rental application includes a background check. Finding a decent job was impossible when every job application asked about felonies. Her path had been eased some by a benefactor, a Dallas businessman who asked to remain anonymous and who had supplied her with work and housing as much as he could.

In 2005, the on-again-off-again love of her life, Billy Cacy, died, and she fell into a dark place. She tried to kill herself with a bottle of Crown Royal, but was discovered on the floor of her apartment and treated for alcohol poisoning in the hospital. Life had taken on a desolate pattern, in which the things she loved were always lost. She struggled with drinking again.

All the while, others worked on her behalf. The Innocence Project of Texas had taken on her case and was pushing for her exoneration. A whistle-blower from the Bexar County toxicology lab had filed suit, alleging wrongful termination and settling for $350,000. Dr. Larry Ytuarte confirmed what Hurst had always suspected — that the lab had manufactured paperwork to patch a chain of evidence broken by mishandling.

In 2005, a new state law directed the formation of the Texas Forensic Science Commission to evaluate claims alleging convictions based on junk science, negligence or misconduct. Politics infected the process.

Cameron Todd Willingham, a Corsicana man, was executed in 2004 for burning his house down with his children inside. Hurst investigated his case and found it to be as bogus as Cacy's. A number of experts agreed. But Texas Attorney General Greg Abbott saw to it that the commission did not review the case, authoring a legal opinion that said it could not review scientific testimony given before the law's passage. That meant they couldn't review Cacy's case either.

Another door opened in fall 2011. The State Fire Marshal's Office, at the urging of the commission, announced that it would review arson cases its investigators had participated in. When Chris Connealy was hired to the post, he empaneled an expert committee of top forensic scientists and attorneys to evaluate the evidence that had sealed arson convictions. On August 1, 2013, the state fire marshal released its review of the Cacy case. The arson determination, the fire marshal's expert panel concluded, was "not supportable under the present day scientific standards of care for conducting a fire investigation." There was "no scientific evidence to support the opinion that William R. Richardson was alive when the fire broke out."

Dr. Charles Bux, who performed the autopsy in Bexar County and is now a coroner in Colorado, believes Richardson was "alive, plain and simple."

"I based it on the arson finding and ruled it a homicide. Until someone has good evidence that's not true, I see no reason to change my opinion."

The district attorney in Fort Stockton, Rod Ponton, has requested that the state attorney general render an opinion on the fire marshal's work. He argues that, like the Texas Forensic Science Commission, the fire marshal has no right to review cases that predate the law. The law, as written, applies only to the commission, state Fire Marshal Connealy counters.

The district attorney who twice prosecuted Cacy, now in private practice in Fort Stockton, remains convinced of her guilt. "I think the decision of the jury finding her guilty was based on some solid evidence..." Valadez said. "They had to consider the facts to decide an appropriate punishment. The second jury almost doubled her sentence."

Retired State District Judge Alex Gonzalez, who presided over both trials, wasn't as confident. "Personally, if the lawyer that handled the second trial came before me instead of the jury, I would have ruled not guilty."

In September, Governor Rick Perry signed into law a bill authored by Senator John Whitmire, which provided an avenue for those convicted on junk science to petition the Texas Court of Criminal Appeals. There are no guarantees. Her attorney, Gary Udashen, Innocence Project of Texas president, is waiting for a hearing in Fort Stockton and, ultimately, before the appeals court. Her first real shot at clearing her name could come as early as April.

Inside a queasy green Motel 6 in White Settlement earlier this month, Cacy's trembling hand held a cigarette to her mouth. She'd been hospitalized days before for recurrent pneumonia, and her 66-year-old bird-boned body had withered considerably. Her lungs rattled as she coughed. She was, on that morning, homeless, having recently moved out of a place in Granbury she had shared with some extended family. She said she had to get out of there, and called it a "bad situation."

In the corner of her small room, she had piled clothing and other belongings she could not take with her on the journey. She planned to catch a bus to Port Aransas, to stay with her son and his family in their RV, and she worried that her two suitcases would be over the weight limit if she didn't cull their contents. Tears leaked from her green eyes. She apologized for crying, and stuffed a gallon bag filled with orange prescription bottles into a carry-on as she repacked. Steeling herself for the call to her parole officer, to inform him she was leaving the county, she took a deep drag from her cigarette and poured two cans of Coke into a plastic cup. North Texas was in the middle of a hard freeze that day, and she was told her parole officer would not be in the office.

She looked over the dim room that had been her home for nearly two weeks, and over the belongings she could not bring with her. Her two suitcases were loaded into a reporter's car, and she set off over a frozen highway, bumping over bridges encased in brown ice. As front loaders rumbled past, scouring the asphalt, she talked about the song her father had written for her, "Sonia Jean, the Sunshine Girl." She spoke about how Richardson always brought white stray cats to her bedside when she was sick as a child, to her delight. Those memories had sustained her when she was locked up. "I thought I was going to die in prison," she said. "Ninety-nine years." They sustain her still.

She calmed down some when she reached the bus station in Fort Worth. With no car, she said she hadn't been sure how she would get there. The driver announced over the PA that the bus to Corpus Christi was boarding. Cacy took a deep breath. She was bound for another new start that she hoped wouldn't end like all the others. The tiny woman stepped out into the cold air and onto the Greyhound bus, smiling, carrying in both hands all she owned in the world.