Did Bad Fire Science Send Tim and Deb Nicholls to Prison?

The fire exploded through the living room of the split-level house in northeast Colorado Springs. Flames moved quickly along walls and furniture, bursting through a picture window and igniting the enormous pine tree outside. Suffocating smoke flooded the home’s interior and pushed into the kitchen and the upstairs hallway and bedrooms.

Samantha Lembergs was among the first to arrive at 4107 Undimmed Circle. It was March 7, 2003, just a few minutes after 2 a.m., and the Colorado Springs Police Department (CSPD) officer had on gloves and a jacket as she approached the burning house. When she got closer, the officer could see the front porch, and everything on it, was on fire. A trail of smoke poured out of an upstairs window; flames spilled out of another.

Two firefighters charged toward the left side of the house, barely registering the injured man on the sidewalk. Tim Nicholls was barefoot and in boxers, covered in soot and sweat. He was badly injured: Burns splotched his back and neck. Both of his corneas were singed. His right wrist was broken from a fall out of an upstairs window. As he sat, less than 10 yards from the fire, his screams could be heard above the crackle of the flames.

Lembergs felt the fire’s heat through her jacket as she rushed to Nicholls’ side. “I can’t see! I can’t see!” Tim yelled. Skin from one of his arms peeled off in Lembergs’ gloved hand as she steadied him. Later, as the officer walked the man to a waiting ambulance, she asked if there was anyone else inside. Tim told the officer that his three children were still trapped in the house.

Clark Gaddie crawled under the home’s partially opened garage door, careful not to dislodge the oxygen pack strapped to his back. The Colorado Springs firefighter yanked a hose behind him and pulled it toward the door that connected the garage and kitchen. As part of the Engine 10 crew, Gaddie already knew the details: A 911 caller had said children lived in the house. Gaddie had been to nearly 700 fires in his 23-year career, and he knew how difficult it was to find frightened children in smoke and flames. Adults ran for doors and windows to escape. Kids hid in closets and under beds and blankets.

Gaddie pressed a gloved hand against the wooden door leading to the kitchen and checked for heat. Behind him were two other Springs firefighters. Gaddie pushed open the door and was immediately hit with a blast of smoke-filled pressure. The firefighters steadied themselves and crawled inside. Gaddie’s flashlight transformed the smoke into a milky haze, but the men could see a line of fire growing on a wall directly above them. Gaddie opened his hose, but the flames wouldn’t recede. The firefighters moved slowly toward the living room, which had reached what is known as flashover, the moment when a fire’s radiant heat becomes so intense that everything instantaneously bursts into flames. “We would have pulled out,” Gaddie later said. “[But] when we’re told there’s kids [inside], we kind of pull all the stops out.”

Multiple firefighters searched the three upstairs bedrooms over the next several minutes. Eventually, 11-year-old Jay was found curled up at the end of the hallway. He was carried out the front door, where neighbors saw his limp body dangling from a firefighter’s arms. Five-year-old Sophia and three-year-old Sierra were found in their parents’ bedroom. Sophia was behind the door, partially covered with a blanket. In the smoke and darkness, firefighters initially mistook Sierra for a doll.

Not long after the three children had been taken outside, Deb Nicholls pulled onto the street in a white Chevrolet Camaro driven by an employee from the karaoke business she and Tim owned. Deb, 35, had been at a nearby bar, auditioning a new karaoke DJ and sharing a few drinks with friends. As she and her designated driver crawled up the street in the car, Deb could see red and blue emergency lights, flames, and neighbors swarming the sidewalk outside her home. At least one neighbor saw Deb run toward the left side of the burning house to get a better look at her children’s bedroom windows. A police officer moved her back; a neighbor lied, telling Deb that the children had been taken out of the house alive. Tim had just left in an ambulance. You need to get to the hospital, an officer told her.

The coroner later ruled Sierra died from smoke inhalation and Jay died from smoke inhalation and thermal burns. Sophia’s brain was badly damaged from the smoke, and she died a short time after arriving at the hospital. Tim had second-degree burns and needed to be helicoptered to the University of Colorado Hospital Burn Center in Denver. Outside the Springs hospital, Deb paced and smoked a cigarette while her mother, Sandra Wilson, attempted to console her. Deb had cleaned the house before leaving for work, she told her mother. She’d lit several candles and left them for Tim to put out before he went to bed. “I killed all my kids,” Deb said.

An hour after firefighters finally extinguished the flames, sometime before 3:30 a.m., the first of at least nine police and fire investigators began searching the house. They’d soon be joined by members of the CSPD Major Crimes Unit, the Colorado Bureau of Investigation (CBI), and an investigator from American Family Insurance, the company that held the Nicholls’ homeowner’s policy.

Over the next few days, investigators worked their ways through the 1,700-square-foot house—taking notes, videos, and photographs. The living room walls were burned black. Part of the ceiling had collapsed, and only ashes and outlines of furniture remained.

When the living room reached flashover, the blaze transformed from what’s known as a fuel-controlled fire into a ventilation-controlled fire—essentially a fire that burns more intensely due to its reliance on the available oxygen rather than fuel. In this instance, the fire on Undimmed Circle needed oxygen and blasted out a front window and onto the porch and a nearby tree.

Ventilation-controlled fires are far more unwieldy and less predictable than fuel-controlled ones and are therefore more difficult to investigate. Fire investigators generally attempt to locate soot marks that resemble a V-shaped pattern along walls. When an object—like a lamp—catches fire, smoke and heat spread outward, creating a distinct “V” that marks an ignition point. But flashover significantly complicated matters. The living room was entirely charred, which eliminated many of the obvious signs that would have led investigators to a likely starting point.

In an interview with police hours after the fire, Deb mentioned the burning candles, but she didn’t have any other substantive information to offer. In the days and weeks after the fire, Tim, who was recovering from burns that covered about 10 percent of his body, was interviewed multiple times in the hospital.

As the 32-year-old answered investigators’ questions, a picture of what happened that night began to emerge: He’d been startled awake around 2 a.m. Jay and Sierra were in their bedrooms; Sophia had crawled into her parents’ bed an hour or two earlier and was sleeping at Tim’s side. Tim walked to the top of the staircase and noticed the house seemed uncomfortably warm. He looked downstairs and noticed the light was off in the living room fish tank. After walking down the stairs, he could see that the stovetop light was out in the kitchen but that a neighbor’s porch light was on.

A house framer by trade, Tim thought a circuit breaker might have been tripped. He walked into the garage, opened an exterior door to reach the breaker panel, then heard a whoosh behind him. A bright light emanated from inside the house. Tim told police he ran into the kitchen, then to the living room, the latter of which was thick with smoke. As he rushed back up the stairs, a piece of ceiling collapsed on him, burning part of his back and neck. Panicked amid the smoke rising around him, Nicholls said he then ran to his bedroom, opened a window to get air, and lost consciousness. He awoke a few moments later, under a window outside the house, with no idea how he’d gotten there.

Based on evidence at the scene, Kirk Schmitt, a Colorado Springs Fire Department (CSFD) investigator, estimated only a few moments had passed between ignition and flashover. The first 911 call came in at 2:01 a.m., and Engine 10 had pulled up six minutes later. Schmitt couldn’t square a burning candle with Tim’s story about the fire and what he now saw around him.

Erin, a Labrador retriever from the CBI trained to detect accelerants that can be used to start fires, did multiple walk-throughs with her handler, an agent named Jerry Means. As the pair walked the ruins of the house, Means gave Erin signals to search. In time, Erin “alerted” in 11 locations, including on part of the living room carpet. Any item Erin alerted on was sealed in a metal container, with the dog’s name on it, to be tested in a CBI lab. A small can of the household multicleaner Goof Off was taken from a basement shelf, as were samples from fuel containers found in the garage. Those, too, were shipped to the lab.

Investigators quickly opened the home to Robert Toth, a contractor who worked with American Family. Insurance companies and law enforcement enjoy a mutually beneficial relationship in fire investigations, sometimes working hand in hand to collect and interpret evidence. (Colorado law mandates that insurers share findings with law enforcement, upon request.) Toth understood the insurance calculus on house fires: Accidental blazes got payouts; an intentional fire set by the home’s resident did not.

After walking through the house, Toth was confounded. Like Schmitt, the former Aurora firefighter couldn’t imagine an unintentional fire burning so hot, so quickly. Toth saw what he later called a “wonderful reservoir for potential ignitable liquids” at one edge of the damaged room. He collected his own samples from the scene and sent them to an independent lab in Texas for testing.

Several weeks after Jay, Sophia, and Sierra had been buried in neighboring plots at a Woodland Park cemetery, Toth continued to work the case. He’d eventually call one of the nation’s leading fire investigators, a Californian named John DeHaan. Fifty-five at the time, DeHaan had investigated hundreds of fires for agencies such as the Bureau of Alcohol, Tobacco, and Firearms (ATF) and was widely considered the field’s pre-eminent expert. He owned a private company, Fire-Ex Forensics Inc., which was based in Vallejo, California, 30 miles northeast of San Francisco. DeHaan had also edited six editions of Kirk’s Fire Investigation, long considered the bible among fire investigators around the world, and specialized in studying fires that involved human deaths.

At the time he got the call from Toth, DeHaan had created a cottage industry by testifying in arson cases. On the witness stand, he was succinct and self-assured; prosecutors often introduced him to jurors as the man who literally wrote the book on fire investigation.

DeHaan accepted Toth’s invitation to come to Colorado Springs. A month after the fire on Undimmed Circle, perhaps the most famous fire investigator in America was standing among the remains of the Nicholls’ living room.

The couple had moved to 4107 Undimmed Circle three years earlier, with three children. There was Jay—Deb’s son from a previous relationship—Sophia, and Sierra, who was only a few weeks old when the family moved into the home. Everything about the neighborhood exuded the suburban ideal: homes with big backyards, mature trees, immaculately maintained strips of open space, and community parks in the middle of it all. Kids walked to the nearby elementary and middle schools on winding streets with names such as Carefree, Nonchalant, Picturesque, Seesaw, and Teeter Totter.

In addition to the karaoke business Deb ran mostly on her own, the Nichollses owned a successful house-framing company. The two were fastidious with their own home, and Tim worked on it whenever he had time. He drove a beat-up truck; Deb got the white Camaro.

The fire stunned the Colorado Springs community. More than 100 people showed up at a church in Woodland Park to mourn the children’s deaths, and Tim left the Denver hospital, where he’d been recovering, so he could attend the funeral. During the service, he wore sunglasses to protect his damaged eyes from the sunlight. At the cemetery afterward, he collapsed on Sierra’s grave.

Even so, Tim, the only person who survived the fire, became a suspect. “We did not want to believe this was intentionally set,” CSPD detective Rick Gysin told the Colorado Springs Gazette in 2008, five years after the blaze. “You don’t want to think of humanity like that.”

However, investigators eventually came to the conclusion that the fire was a triple homicide. CBI tests on the carpeting, on Tim’s sneakers and jeans, and on pajamas belonging to both Sophia and Sierra had come back positive for xylenes—colorless, flammable liquids that could be used as accelerants in fires—which gave investigators reason to believe the fire was intentionally set.

On top of that, Tim’s recollection of the fire changed with each retelling. At one point, he said he’d walked to the garage and returned to a living room filled with fire; in another, it was heavy smoke. In one, he ran to a bedroom window to get air; in another, he was lining up his children to get out of the house. “What Tim Nicholls said didn’t make a lot of sense,” Derek Graham, part of the police homicide investigation team, told the Gazette in 2008. “That was a big red flag from the beginning.”

Investigators interviewed other witnesses, including Irma Woodworth, a neighbor who described Deb as devastated by her children’s deaths. Yet over time, an increasing number of people would offer statements that portrayed the couple negatively. Eventually, Deb would get drawn into the investigative web that had already ensnared her husband.

She hadn’t attended her children’s funeral, a fact that investigators noted with suspicion. But even seemingly innocuous details about Deb were scrutinized, too. An American Family Insurance investigator who interviewed Deb days after the fire recalled she wore a tracksuit and that her nails were painted red. The investigator also remembered Deb showing up outside the burned house with what appeared to be a new hairdo. One homebuilder remembered a phone conversation in which Deb cried over the family’s dog, which had died in the blaze.

Yvonne Valdez, one of Deb’s neighbors and best friends, remembered watching a distraught Deb attempt to fight police who prevented her from seeing whether her children’s back bedrooms were engulfed in flames. Valdez also detailed phone calls after the fire in which Deb was inconsolable.

But over time, Valdez started to tell investigators a different story. For years, Deb had battled weight issues. In 2000—after Deb had had a breast reduction, taken various medications, visited nutritionists, and tried different diets—Valdez suggested Deb try methamphetamine as a way to help her lose weight. Deb eventually started using meth habitually and lost around 100 pounds.

Valdez herself used meth, occasionally supplied it, and once unsuccessfully attempted to manufacture it in her house on Undimmed Circle, where she lived with her son. After a year of regular use, Valdez testified, Deb had built up a habit that, at one point, cost her $500 per week. The narrative of a drug-addicted wife and mother suddenly desperate for money gave investigators a possible motive, but the most damning accusations came from Deb’s mother, Sandra Wilson. A psychologist who’d abandoned her six children during their childhoods, Wilson had reconciled with Deb, but the relationship later became strained. Wilson argued often with Deb and claimed Tim had used methamphetamine with his wife. She said Deb struggled with parenthood and that she’d suddenly decided she wanted a lifestyle free from the constraints of her children.

Despite the case investigators were building against the couple, District Attorney Jeanne Smith, of the Fourth Judicial District, declined to file charges against Tim or Deb. A former deputy district attorney, William Bain, told the Gazette in 2008 that Smith was hesitant in part because the case was heavily reliant on circumstantial evidence. (Smith declined to comment.) “It would have been one thing if we had a confession from Tim Nicholls,” Bain, who is now a district court judge, told the Gazette in 2008. “There was no way to prove that case beyond a reasonable doubt.”

In the fire’s aftermath, Tim and Deb moved from a hotel to a rental house. Tim had always seen himself as the fixer in the relationship, but the couple struggled. He’d met Deb at a karaoke bar in Woodland Park in 1994 and soon found himself enamored of Jay, who was two at the time. Tim had grown up without a father figure for much of his life, and he didn’t want the same circumstance for the little boy. “I think he married Deb because he loved Jay so much,” Tim’s stepfather, Rick Broce, says.

At their rental home, the two vacillated between wanting to talk about their children and wanting to walk out the door and never come back. When Deb wanted to talk, Tim didn’t. When Tim wanted to talk, Deb didn’t.

One day, Tim framed their children’s photos and hung them on a living room wall. Deb walked into the room and fainted.

Tim and Deb separated in the summer of 2004, a little more than a year after the fire, and later filed for divorce. Tim stayed in Colorado Springs and continued to work in home construction, despite having shuttered the family’s house-framing business. He entered into a brief relationship and had a child with another woman. Deb moved to Traverse City, Michigan, where she’d grown up, and lived with her father.

Smith, the district attorney, was term-limited and replaced by John Newsome, a former prosecutor in the office. Newsome turned the office’s attention to the Nicholls case at the urging of police investigators and Deb’s mother, who’d written Newsome after his election, in 2005. (Newsome did not respond to a request for comment. Wilson died in 2015.)

On July 21, 2005, a grand jury indicted Tim based, in part, on evidence showing xylenes had been discovered during the fire investigation. Police arrested Nicholls while he was at work. He was taken to the Colorado Springs jail, where he shared a cell with a 41-year-old career criminal named Hiram Church, who’d previously worked with law enforcement as a jailhouse informant. Within days, Church sent a message to detectives that he had information to share.

During several conversations with investigators, Church claimed Tim had not only admitted to setting the fire that killed his children, but also that he told Church his wife had put him up to it. In Church’s retelling, the husband and wife conspired to commit the crime, with Tim spraying Goof Off throughout the house—including on a living room couch and in an outside vent.

The motive, Church said, was simple: The couple’s relationship was strained, in part because Deb owed a number of different people drug money. With their relationship already headed toward an end, a fire would allow them both to reap an insurance windfall and give them a way to restart their lives. Law enforcement officers believed the story. Within days of his first conversation with investigators, Church was released from jail on a personal recognizance bond that left him free to roam, without posting bail, until his next court date.

Tim’s trial began on March 19, 2007, and lasted almost six weeks. It included more than 20 prosecution witnesses, including Church, the fire investigator DeHaan, and Tom Netwal, a CBI chemist who’d reviewed burned samples found in the house. Netwal testified that samples initially identified by Erin, the CBI’s dog, were positive for xylenes. Tests of the burned material also suggested that Goof Off could have been used as an accelerant.

Schmitt, the CSFD investigator, described the char pattern he saw at the bottom of the living room stairs, which to him indicated an accelerant had been used to speed the spread of the fire. Means, the CBI canine handler, talked about the reliability of his dog, which Netwal reinforced, claiming to jurors that the canine’s sense of smell was more sensitive than the CBI’s own analytic devices. Wilson, Tim’s mother-in-law, portrayed a marriage derailed by drug abuse and Deb’s immaturity. Church testified that Tim had told him about spraying Goof Off and that the couple hoped to collect an insurance payout. (In a court filing, a second inmate said that Church bragged that a jailhouse confession was his “get-out-of-jail-free card.”)

DeHaan testified the fire burned too hot and too fast to match Tim’s re-creation of the events and Deb’s claim that a candle could have started the blaze. Using thermal estimates based on the room’s size—plus the locations, sizes, and distances between furniture—DeHaan said it would’ve been impossible for a single fire in the room to move to nearby pieces of furniture.

Tim’s defense relied heavily on John Lentini, a fire expert from Florida, who routinely squared off against DeHaan in court. Lentini portrayed DeHaan’s work as incomplete, at best, and added that the CBI’s chemist misidentified compounds in burned items analyzed from the house; that fire investigators misread the scene; and that it was impossible to confirm the CBI arson dog’s accuracy.

On May 1, 2007, four years after the fire, a jury found Tim guilty on more than a dozen counts, including three charges of first-degree murder (felony murder), child abuse resulting in death, and animal cruelty involving the family dog. The jury found that Tim was innocent of conspiring with his wife to kill their children. He was sentenced to three consecutive life terms and sent to the Sterling Correctional Facility on Colorado’s Eastern Plains. “This is the second-saddest day of my life,” Wilson said afterward. “The first was when I lost those kids. The horror is, I believe it’s true…. I’m here for Jay, Sophia, and Sierra. My wish is that they now rest in peace.”

Despite the jury’s finding that Tim was not guilty of conspiring with his wife to kill the children, Deb was indicted seven months after Tim’s conviction. Deb had returned to Colorado Springs two years earlier, in 2005, in an attempt to restart her life in the city.

At her trial, in 2008, prosecutors relied on testimony from her mother and Church to link Deb to a conspiracy to kill the three children and burn the house for money. The American Family Insurance investigator testified about Deb’s red fingernails. Valdez, the neighbor and former friend, detailed Deb’s methamphetamine use. A police investigator who’d interviewed Deb hours after the fire recalled that “she’d act like she was crying, but there were no tears.” Wilson testified that her daughter didn’t attend the funeral and that her son-in-law wore sunglasses during the service. In addition to witness statements, prosecutors relied on the same fire science used at Tim’s trial the year before. Again, DeHaan connected the dots for the jury.

“We know what Jay, Sophia, and Sierra had become: impediments, chores, responsibilities that… she just couldn’t handle anymore,” assistant district attorney Amy Mullaney told jurors. “This is not a case… about poor, helpless Deb Nicholls, who, through no fault of her own, having a part in this, is ending up in the chair in which we now see her sitting. It’s not a case about a woman, through no decision of her own, being whisked up by the hand of fate and plunked back down into the middle of a drug and partying lifestyle. And it’s not a case about a horrible accident. This is a case about meth, about money, and about murder in cold blood.”

In November 2008, the jury found Deb Nicholls guilty on three counts of first-degree murder. She was sentenced to three life sentences and sent to the Denver Women’s Correctional Facility (DWCF).

Both Tim and Deb filed appeals, arguing that prosecutors improperly applied the available fire science and relied on an unreliable jailhouse informant in their cases. Both appeals were rejected by the Colorado Supreme Court, generally the last place where a conviction in the state can be overturned.

But one Boulder defense attorney, Gail Johnson, knows that failed appeals don’t always signify a defendant’s guilt. In 2016, Johnson secured an exoneration for Clarence Moses-El, a Denver man who’d been convicted in 1988 of assault, sexual assault, and burglary and had been sentenced to 48 years in prison. After she met with Tim at the Sterling Correctional Facility, Johnson pored over thousands of pages of trial transcripts. “It was pretty obvious to me he didn’t do it,” Johnson says.

Deb, meanwhile, had been talking about her case with her father, Douglas Baumgardner, who had spoken with his daughter on the phone every day since she’d been sent to prison. Between check-ins and I-love-yous, Baumgardner scribbled notes on a yellow legal pad as he spoke with his daughter about a potential legal challenge.

Baumgardner had read about other arson cases in which the investigations mirrored the one at Undimmed Circle. There was Cameron Todd Willingham, a Texas man executed in 2004 for the arson deaths of his three children. Willingham was convicted, in part, based on fire science that included the similar too-hot-too-fast argument for flashover. A post-execution review of his case by fire experts determined Willingham likely did not commit the crime and instead was the victim of a shoddy investigation.

Another disturbingly similar case involved Amanda Gutweiler, who was indicted for the 2001 arson murders of her three children in Louisiana and faced the death penalty. Prosecutors questioned her lifestyle (Gutweiler’s three kids had different fathers), said she no longer wanted to be a mother, and argued she had killed the children for an insurance payout.

Just as in the Nichollses’ cases, DeHaan was brought in as an expert in the Gutweiler investigation and said in two different reports for prosecutors that accelerants must have been used in multiple areas to achieve flashover. Prosecutors later learned that there was no evidence of accelerants and that the crime scene had been compromised. The DA’s office then asked DeHaan to file a third report. In that account, DeHaan claimed he performed further tests and determined the fire’s origin was inconclusive. Gutweiler was released after spending four years in jail awaiting trial.

Deb had been in prison for 11 years awaiting a break in her own case—one that she and her father weren’t sure would ever come—when she learned Tim was visiting the DWCF. He was building sets for the University of Denver’s Prison Arts Initiative, which had brought a production of One Flew Over the Cuckoo’s Nest to the prison. Tim got to attend the performance as part of his work with the group, which used inmates from Sterling as cast and crew.

Before the play began, Deb spotted Tim. A guard allowed the two to speak for about 20 minutes; it was the first time they’d seen each other in more than a decade. The pair talked about their children and asked each other how they were holding up. Tim pointed out Johnson, his new attorney, who was in the audience. He said Johnson thought there might be another avenue for an appeal. In fact, he told his ex-wife, his attorney thought Deb had the better chance for success.

In April 2019, defense attorney Janene McCabe drove from Boulder to the DWCF to meet Deb. McCabe had been assigned the case after Deb wrote an appeal and a judge suggested she get professional legal representation. The prison sits on the northeast end of Denver, amid brown fields and aging warehouses. By that time, Deb had spent more than a decade of her life in the prison’s maximum-security unit, where she shared a single-windowed cell with another inmate and worked in the prison library. As McCabe and Deb met in the prison’s visitation room, the attorney thought Deb looked exhausted. Now 51, her hair was showing signs of gray.

Deb survived her days in prison mostly by distracting herself from the monotony of day-to-day life. In addition to her work at the library, she painted with watercolors and rode a stationary bicycle dozens of miles a week in the prison exercise room. Deb often thought about her children: her “mama’s boy,” Jay; Sophia’s serene nature; the happy click-clack of Sierra’s plastic Disney princess shoes echoing through the house.

She cried during most of her first meeting with McCabe, who’d spent weeks reading up on Deb’s case. “There was a lot of bogus science and bad investigative work obvious right from the beginning,” McCabe says. The attorney was also confounded by authorities’ deference to the CBI’s canine and to Church, the jailhouse informant.

As the pair sat together, Deb told her attorney about her family’s life before the fire, and about the aftermath. “Deb struck me as a typical Midwestern housewife,” McCabe says. Nothing about the woman in front of McCabe matched the story prosecutors told jurors at the trial. “It didn’t compute,” McCabe says. “Like, this is the meth addict who burned her house down and killed her kids and planned it with her husband?”

McCabe briefed Deb on their legal options. Based, in part, on scientific evidence, Deb could file what’s known as a 35(c) motion. A 35(c) of the Colorado Rules of Criminal Procedure allows defendants to raise “collateral attacks”—essentially presenting new evidence not previously available—with the original trial court, even after they’ve exhausted their rights to direct appeals elsewhere.

In this case, McCabe would largely focus on DeHaan, the fire expert who’d by that time been discredited for erroneous work in the Gutweiler case. DeHaan had not only initially claimed the Louisiana blaze was the result of separately ignited fires but also incorrectly calculated how much heat the burning furniture needed to generate to reach flashover. He added that the fire burned too hot and too fast to match witnesses’ retelling of events, which he said meant an accelerant had to have been used, although none was found. As with the Nichollses’ cases, DeHaan also used the concept of negative corpus—that is, because he could not determine an accidental cause, the fire could only be arson.

If a judge accepted the 35(c), McCabe explained, the decision could clear the way for a new trial for Deb. But getting a retrial based on new evidence is exceedingly difficult. Minus convincing new evidence—newly tested DNA, for example—the American legal system is set up to have a judge or a jury be the final arbiter, with very little post-conviction wiggle room. “Appeals are virtually useless in unraveling the falsehoods that came forward at trial,” says Marc Howard, a professor of government and law at Georgetown University who heads the school’s Prisons and Justice Initiative, which aims to educate people about mass incarceration and is a leading criminal justice legal reform organization. “There’s a big myth about appeals. You think that means [a defendant] is going to be able to have another crack at making their case, but it’s over. Anything that gets admitted at trial is fact. Even if it’s lies, impossibilities, and junk science, it becomes fact.”

In a November 2013 hearing for Tim’s appeal, Judge G. David Miller was reluctant to move forward because he believed evolving fire science was not compelling enough to order a retrial. This wasn’t the “classic fingerprint missed at the scene by the cops…. Nor is it DNA,” the judge said at the hearing. “Science is constantly evolving in all fields. And one could make the argument in many, many, many cases that there’s been an evolution of some aspect of the scientific testimony that was provided a year ago, five years ago, 10 years ago.” DNA evidence, the judge said, was a “show-stopper.” Miller ultimately rejected Tim’s request for a new trial. The Colorado Court of Appeals affirmed the decision, and the Colorado Supreme Court later declined to review the judge’s ruling.

Still, there was hope for Deb. Since 1989, more than 79 people in the United States have been exonerated in arson cases. In 53 of those exonerations, there was false or misleading forensic evidence that had led to an initial conviction. If McCabe could make a strong enough argument in the 35(c) motion, she believed it could increase the odds of Deb getting a new trial.

McCabe was working in her office one day in the fall of 2019 when she got a call from Johnson, the attorney who was representing Tim. Johnson had learned that the Korey Wise Innocence Project (KWIP), at the University of Colorado Law School, was evaluating cases that had strong non-DNA evidence as the backbone for an appeal. Deb’s case seemed to be a fit for KWIP.

In the 2000s, before Tim’s trial, Barry Scheck, co-founder of the Innocence Project, a national litigation and public policy organization that has funded appeals and expert testimony in hundreds of exonerations, formed an arson review committee to examine cases where defendants claimed they were wrongfully convicted. The work eventually would help focus court challenges based on non-DNA evidence where strong scientific components existed. In subsequent years, attorneys have had success overturning arson convictions across the country. Since 2013, according to data from the National Registry of Exonerations, at least 27 people convicted of arson-related murders have been exonerated.

McCabe contacted Anne-Marie Moyes, the executive director of KWIP. “I was immediately intrigued,” says Moyes, who’d read trial transcripts and reports and reached the same conclusions as McCabe. She noted much of the work on Undimmed Circle went against best practices from the National Fire Protection Association, a nonprofit that helps set standards for fire investigators. “I thought it was very straightforward,” Moyes says. “You have bad science, a jailhouse snitch, an arson dog—all those things that can be challenged because they’re just wrong.”

Moyes called a meeting with the Korey Wise board at CU and then phoned McCabe. KWIP wanted in.

The fire science angle would serve as the basis for Deb’s 35(c) motion. For decades, defense attorneys across the country have chipped away at myriad myths underlying fire investigations, proving them to be consistently unreliable. The National Fire Protection Association has also attempted to remedy the unreliability of those investigations. In 1992, the group published NFPA 921, a pioneering guide that the organization hoped would help transform the field. Rather than relying on instincts and visual interpretations of scenes, NFPA 921 advocated for the scientific method and encouraged investigators to examine all evidence from a scene before making determinations about a fire’s origin and cause.

Perhaps the most famous denunciation of what was then accepted fire science occurred in 1991, in what is known as the Lime Street fire re-creation. At the time, a 35-year-old man named Gerald Wayne Lewis was suspected of killing six people, including his wife, in a house fire in Jacksonville, Florida. Investigators discovered what they believed were obvious signs of arson.

Lewis said the fire had started accidentally on a living room couch where his son had been playing with matches. A police chemist reported the presence of gasoline on Lewis’ clothing. He was charged with six counts of murder and faced the death penalty.

Testing by fire investigators later revealed the gasoline conclusion was incorrect. Prosecutors turned to Lentini and DeHaan, who both thought Lewis’ explanation was implausible. The pair was given access to a condemned house next to Lewis’ home and produced an elaborate re-creation of the fire.

Without using a liquid accelerant, such as gasoline, Lentini and DeHaan set a couch in the home’s living room on fire. They watched in astonishment as flames quickly took hold, tearing through the couch, then sending a column of smoke upward that hit the ceiling and spread a thick layer of hot gas overhead. Within three minutes, smoke was running down walls and filling the room. The temperature skyrocketed, and the room exploded into flames. Windows shattered. From a single ignition point on a couch, the room reached flashover in barely more than four minutes.

The men examined the living room and hallways afterward. Irregular spots that resembled pour patterns appeared on the burned floors. Pour patterns had once been a telltale sign of arson, but the test had proven they could occur as a result of flashover. The charges against Lewis were dropped.

Fire investigations across the country, however, continued to be woefully inaccurate. In 2006, 53 of the nation’s top fire investigators met at a soon-to-be-demolished hotel east of the Las Vegas Strip. ATF instructors created two, 168-square-foot rooms with open doorways in the hotel’s parking lot. They gathered similar queen beds, dressers, nightstands, and tables for each room. They then set fires at each end of the beds and let the fires burn for seven minutes. Afterward, instructors asked investigators to identify the 42-square-foot area from which the fires had originated and spread to other areas.

Just three out of 53 investigators successfully picked the correct section in the first room. Another three of 53 picked the correct section in the second. “And it was a different set of three people,” says Steve Carman, a former ATF special agent who helped organize the test and now is president of Carman & Associates Fire Investigation in Grass Valley, California. In other words, seasoned investigators picked the correct area less than six percent of the time. “What we recognized,” Carman says, “is there’s a problem.”

Chief among the issues, Carman says, is that investigators had been trained improperly, in many cases by colleagues who’d begun their careers in the 1960s and ’70s, when hunches and theories often trumped scientific reasoning when it came to fire dynamics. “The people who seemed to have the hardest time were the ones who’d done this for 20 or 30 years,” Carman says. “What is the commonality between all those people? Number one is most of them think they know everything and they don’t need to learn.”

Many of the investigators called to the scene on Undimmed Circle in 2003 had worked fires for decades. The most tenured among them was DeHaan, who’d been a criminalist for more than 30 years by the time he arrived in Colorado Springs. He’d been called by dozens of prosecutors over the years to investigate potential arson cases. At one point, he worked with the Discovery Channel to investigate the 1871 Great Chicago Fire.

Although he came to the Nicholls case at the request of American Family Insurance, DeHaan became an investigative cornerstone for Colorado Springs prosecutors. At the trials for both Tim and Deb, DeHaan ended up answering questions that fell well outside his range of expertise. In one instance, he was asked to diagnose the severity of the burns Tim suffered. Despite not having a medical degree, DeHaan called them superficial. In another, he was asked about canine behavior, specifically why the Nichollses’ dog didn’t bark to alert the family to the fire.

Despite the 2006 test blaze in Las Vegas that fire investigators had studied, DeHaan told jurors in both Tim and Deb’s trials in 2007 and 2008, respectively, that it was impossible for a single item—such as a burned couch—to initiate the kind of destruction he saw on Undimmed Circle. Indeed, in the years before and after the Colorado Springs fire, DeHaan investigated myriad blazes nationwide, and “fast and hot” repeatedly appeared as a centerpiece of his work.

He offered key evidence in several cases that subsequently came under question, including the case of Curtis Severns, who was sentenced to 27 years in prison in 2007 for intentionally setting his Plano, Texas, gun shop on fire. Two other experts believed that a frayed electric cord found at the scene created a chain reaction that burned down the building. Two years after the conviction—and two years after Deb had been sent to prison—DeHaan admitted to the Texas Observer that it was “theoretically possible” that the fire was accidental. Severns remains in prison.

There was also the Gutweiler fire in Louisiana. Calling the initial investigation “pretty dreadful,” DeHaan nonetheless examined grand jury testimony from witnesses who saw the fire and from others who said they’d been in the house before the fire and could describe its furnishings. He used that information, in part, to make the prosecution’s argument that the fire was intentional. He later changed his conclusion and wrote a final report claiming he’d performed additional lab tests that disproved his earlier findings. When an investigative committee from the American Academy of Forensic Sciences questioned his report, DeHaan admitted he’d never run those additional tests. To Deb’s attorneys, there were far too many similarities between DeHaan’s work on the Gutweiler case and the methodology he used and the conclusions he reached at Undimmed Circle.

In 2015—three years after the Colorado Supreme Court rejected both Tim’s and Deb’s appeals—the American Academy of Forensic Sciences issued a 26-page report that recommended DeHaan “be expelled from membership” for acting “unethically by inaccurately bolstering his own conclusions and testimony.” The report added that DeHaan’s “conduct dilutes the public’s confidence in the honesty and integrity of forensic scientists and the community as a whole, and perverts our system of justice.” DeHaan resigned from the organization. He died in May 2022. Five months later, Deb’s attorneys filed the 35(c) motion.

McCabe and Moyes believed prosecutors at Deb’s trial had swayed the jury with a barrage of misinformation and misdirection. Even the most basic motive—that Tim and Deb killed their children for an insurance payout—fell apart when the facts were laid out appropriately. “Everything about this case is speculation,” says Kathleen Lord, a KWIP staff attorney who is handling much of Deb’s case. “And the things [prosecutors] relied on to establish arson are now demonstrably unproven.” (Through a spokesperson, Colorado Springs prosecutors declined to comment.)

Not only did the couple not have life insurance for their children, they’d also secured a $28,000 home equity line of credit to fund improvements on their home before the fire. The house had new appliances, a new furnace, new carpeting, and an entirely renovated backyard that included an enormous play area for the children. At most, Deb’s attorneys estimated, the Nichollses would have gotten $10,000, beyond the replacement value of the home, if the house burned in an accidental fire.

Deb’s attorneys also considered the purposeful misdirection of evidence that was allowed in the original trials, which they claim was a sleight-of-hand tactic used to confuse jurors. There was no evidence, for example, that Deb’s methamphetamine use ran her afoul of drug dealers; there was also no proof that Deb was spending $500 a week on meth, as her former neighbor once suggested.

Maybe most critically, prosecutors relied heavily on the CBI chemist’s testimony involving xylenes and Goof Off but failed to mention that American Family Insurance’s laboratory results didn’t find accelerants in its tests. Furthermore, Deb’s 35(c) motion required that the CBI undertake an investigation of its own data in 2023. That examination revealed a consequential finding: Although xylenes had been found during the initial fire investigation, the CBI said they may not have been the byproduct of Goof Off. Instead, the report said that, contrary to a long-held belief by fire investigators, the xylenes could have been produced simply by objects burning at a very high temperature. Put another way, the presence of xylenes was insufficient evidence to conclude that the fire had been purposely set.

If the CBI’s new testing couldn’t confirm the use of an accelerant, then Goof Off couldn’t be proven to have been used to start the fire. The lack of Goof Off in turn cast doubt on the jailhouse informant, who claimed Tim told him the product was used in the fire, which ultimately tied Deb to the conspiracy to burn the house down and kill the children.

Further, investigators didn’t collect a sample of unburned carpet found under a destroyed bookcase, which could have been tested to see if its chemical release matched the rest of the burned samples. Authorities also didn’t collect a living room lamp, which investigators noticed had a frayed cord but didn’t investigate further.

Investigators testified that Erin, the CBI’s canine, was extremely reliable; the investigative team also often repeated that the dog’s ability to sniff out accelerants can exceed laboratory testing capabilities. Deb’s defense argues in a supplement to its original 35(c) that only a few of the canine “alerts” in the house yielded a confirmation in laboratory testing—and even in those positive cases, “trained canines cannot distinguish between hydrocarbons in ignitable liquids and hydrocarbons that exist at any fire scene when furniture and other items decompose at high temperatures.” Additionally, the attorneys argue, investigators were swayed by Erin’s alerts and built an arson case in large part based on the dog’s work. In fact, NFPA 921 declares that canine alerts are speculative and “should not be offered as direct or circumstantial evidence of the presence of an ignitable liquid in a criminal or civil trial.” Colorado Springs prosecutors, through a spokesperson, declined to comment on the case because there are active motions.

Following his initial investigation at Undimmed Circle, Toth, the American Family Insurance investigator, claimed he’d performed his own tests involving candles and the spread of fire, which he said debunked the candle theory. But at Deb’s trial, he admitted he hadn’t recorded any of the tests and couldn’t prove they’d actually been performed.

This summer, it was announced that Deb’s motion would be heard again in a Colorado Springs district court, with the original judge having recused herself. In October, senior judge Deborah R. Eyler of Pueblo was selected to preside over the case. If the motion proves convincing, hearings could begin in early 2024. Because Deb’s case shares many of the same underlying facts as her ex-husband’s, Tim might have a similar path in court.

Tim is now 57. He’s built sets for his prison’s theatrical productions and trains dogs. So far, he’s spent more than a third of his life in prison, “hanging around people I probably wouldn’t have picked in my regular life,” he says in a phone call from the Sterling Correctional Facility. He talks to his mother and stepfather regularly. They’re keeping a room in their Woodland Park townhome for him.

He thinks often about his kids. He thinks about the old neighborhood, how the place on Undimmed Circle was the couple’s first real home. “We upgraded pretty much everything,” he says. New windows and doors; new carpeting and kitchen cabinets. They put in a sprinkler system. Tim built a sand pit for the kids. He redid the deck and built a miniature playhouse. “We made it a nice home,” he says.

Jay would be 31 now; Sophia 26; Sierra 24. Tim thinks about fishing trips with Jay, how the two would visit comic book stores together. He thinks about Sierra, his “daddy’s girl.” He remembers Sophia. He was at her elementary school one day, talking with someone, when he noticed his daughter had disappeared. He looked everywhere, then finally found her with a friend. “A little boy scraped his knee, and there she was, talking to him, occupying this kid’s mind so he wouldn’t think about how his knee hurt,” Tim says. He pauses. “That was so awesome. She had this amazing soul.”

The fire still occupies his thoughts. Tim remembers climbing the stairs, back up to the hallway. “The smoke’s following me,” Tim says. “It’s filling every available space.” When he opens the bedroom window, there’s smoke billowing past his head. The next thing he recalls is waking up outside to a nightmare.

Deb remembers seeing her children in the hospital, how Sophia looked like she was sleeping, how her body had just one small burn on her leg. “That was it,” Deb says. She’s not mad at Tim for not getting the kids out. “I can’t put myself in his shoes,” she says on the phone from DWCF. “I’m not bitter or angry at him.”

In addition to the daily phone calls, her father tries to visit her a couple of times a year. Some of her siblings initially took their mother’s side but have now reconsidered. Sandra Wilson died from cancer, in 2015, and is buried next to her grandchildren. Wilson’s headstone reads, “The best grandmother ever.”

Deb often daydreams about what she’d do on her first day of freedom. She’d hug her father and thank him for believing her. She’d bake key lime and coconut pies for her attorneys. She’d visit her children’s graves. She’d find a way to visit the ocean. In her mind, swimming is the physical manifestation of freedom, a body unencumbered by constraints.

In the meantime, she’ll work in the library. She’ll ride the stationary bicycle. She will paint. Deb’s almost finished her latest work, which is titled, “When I Look to the Sky.” It’s a reference to a Train song that was released the year her children died. The song’s lyrics deal with love and loss, about things taken away and replaced with memories.

The painting is of a wooden pier stretching far out into ocean waves. The sun is hiding somewhere, its golden hues illuminating the sky. In time, Deb says she will add a bicycle and a middle-aged woman at the end of the pier. The woman will have her hands extended skyward. She’ll be looking far in the distance, beyond the limits of the canvas, and into a vast openness only she can see.