Arson convictions are getting thrown out. Experts blame ‘junk science’

Evolving fire science is calling into question some arson convictions in Michigan, with several people being granted new trials or being exonerated after their previous convictions were thrown out.

At least eight people have been exonerated or have received new trials across the state since 2012 based on what the Michigan Innocence Clinic calls “junk science” or what it considers debunked investigative methods. Some of those include what experts now say are discredited practices, such as interpreting physical markers like alleged accelerant pour patterns as being a sign of arson, a sheen on water meaning an accelerant was used or an arson dog alerting to the presence of an accelerant without a lab corroborating it.

Another outdated theory is that melted aluminum under a door sill means gas indicates arson because gas had to have been poured, resulting in a fire so hot that it melted the precious metal, experts said.

Most of the exonerations were for arsons that resulted in people’s deaths, which is what the Innocence Clinic focuses on.

One of those cases involves a Detroit man who was granted a new trial in March after serving nine years in prison for allegedly setting his ex-girlfriend’s home on fire. A Wayne County judge found his 2017 arson conviction relied on a “flawed, unreliable and scientifically invalid fire investigation.”

More: Detroit man jailed 9 years for arson gets new trial, released on bail

Penalties for arson cases can be severe. First-degree arson is punishable by any number of years in prison up to life behind bars, while second-degree arson can result in up to 20 years in prison.

Imran Syed, a law professor at the University of Michigan and co-director of the Michigan Innocence Clinic, estimated more than 1,000 people across the country have been wrongfully convicted of arson based on flawed science.

“I’d hope fewer and fewer people are being charged today based on junk fire science, but I know it’s not going to be zero,” Syed said. “We still see people getting it wrong, but we see them kind of acknowledging it, trying to say why (their old technique) fits in the new guidelines, trying to do old techniques under old standards.”

Some local fire departments have their own fire investigators, who often receive specialized training. Others will seek help from sheriff’s offices or the Michigan State Police, which have offered formal fire‑investigation training since 1980 and have trained more than 2,000 investigators.

Westland Assistant Chief Fire Marshal Kelly Eggers said it was “news to me” that some fire investigation techniques have been debunked or are no longer seen as valid. Westland has three fire investigators.

“From my perspective, not much has changed,” Eggers said. “There’s a technology piece that helps us document scenes, making it a lot easier as far as specifically photographic evidence.”

Taking a second look at arson convictions

To prove arson in Michigan, prosecutors must show that a defendant damaged or destroyed a structure, dwelling or personal property by fire or explosives; that the fire was deliberately and intentionally set; and that the defendant acted deliberately and maliciously with the intent to burn, damage or destroy the property.

Fire investigator Robert Trenkle of Redford Township is well-versed in fire investigations, working across the country to take a second look at potentially faulty arson convictions. He questioned the ability of some fire departments to adequately investigate arson cases, especially smaller departments.

Trenkle was a Detroit fire investigator for more than two decades and said he knows he has more experience investigating arsons than most, given Detroit’s history, which includes hundreds of annual Devil’s Night arsons around Halloween from the 1980s through the early 2000s.

He said he often sees investigators who either don’t know what they’re doing or inaccurately label fires as arson.

“There’s nothing wrong with saying I don’t know (what caused a fire),” Trenkle said. “It’s so simple to not be wrong. If you don’t know it’s an arson, if you don’t know it’s accidental, it’s OK. ‘I don’t know’ doesn’t put people in jail and doesn’t stop them from getting insurance claims.”

Small towns, especially, are more prone to this, Trenkle contended, since their employees spend their careers “not doing and not learning” fire investigation techniques.

In the 1980s and ’90s, Syed said they could argue that the people involved may not have known better. But in more recent cases, people should know the science and some techniques they’re using are outdated, he said.

“I have no doubt there are people conducting unscientific investigations today, either because they’re unaware of the science or because, despite the science, they think they know better,” Syed said.

Richard Meier, a fire investigator with Palmetto, Florida-based Meier Fire Investigation, said he, too, sees investigators using old or bad science.

“In cases like that, somebody is being charged with a crime that never actually occurred,” Meier said. “Even when I started getting involved in fire investigations 15 years ago, there were still people kicking and screaming and being drug into the 21^st century who didn’t want to change their ways. … I have done a number of cases where, fortunately to date, I’ve been able to keep people out of prison when it’s not an actual crime.”

Westland’s Eggers said it’s far tougher to pin the arson on a specific person than to prove that arson occurred. He said that when investigating an arson, he will try to identify potential ignition sources and develop a hypothesis about how the source may have come into contact with the burned areas. He’ll collect evidence samples and send them to the Michigan State Police’s laboratory so lab employees can test for accelerants.

Eggers said arsons are “more prevalent than you may expect.” In 2025, he estimated Westland had about 50 fires, half of which officials believed were intentionally set.

Meier, however, said intentional arsons are rare, accounting for about 4% of fires, and these are largely in vehicle fires where someone sets a stolen vehicle on fire to destroy any remaining evidence in a crime.

“Arson for profit is actually fairly rare, despite what insurance companies want you to believe,” Meier said.

A Wayne Co. conviction goes to trial again as defendant claims flawed evidence

Of the eight cases where a defendant convicted of arson has either been exonerated or granted a new trial, William Whateley’s case is the most recent.

Whateley was convicted of arson for a 2017 fire inside his ex-girlfriend’s Westland trailer. In March, Wayne County Circuit Judge Chandra Baker-Robinson granted him a new trial and allowed him to be released on bond.

Whateley’s attorneys said the investigation into the fire relied almost entirely on outdated and unreliable markers that were once believed to be arson indicators, such as purported pour patterns in the front half and living room of the trailer and an uncorroborated K-9 alert, to determine that the fire was intentionally set.

“I know the jury’s decision in arson cases hinges heavily on what the expert says because the average person does not know how to figure out whether somebody started a fire or not,” Baker-Robinson said when she granted Whateley a new trial. “If you have flawed testimony on whether someone started an arson or not, that’s huge.”

Wayne County Assistant Prosecutor Kirsten Kelly said in March that the county plans to try its case against Whateley again and believes there is enough circumstantial evidence to gain a conviction.

How fire science has changed

The Detroit Fire Department has 16 fire investigators as well as a joint task force with the police department when it comes to investigating fires, Fire Commissioner Chuck Simms said during a budget session with the Detroit City Council earlier this year.

The city investigates around 2,000 fires per year, said Dennis Richardson, chief of the agency’s investigations division. In 2025, 19% (327) of the fires were determined to be arson. In 2024, 18% of the fires were found to be arson.

Richardson said over the years there have been “countless advances and changes in how we conduct our investigations.” He’s been in the arson division since 2003 and said he’s seen the National Fire Protection Association book with the investigations guide grow from 30 pages to being about an inch and a half thick.

“Things we once may have thought to be true may no longer be true, as they may have been debunked through time and additional scientific research,” Richardson said. “Fire investigation was not necessarily considered to be a science when I first started. It was more so an art form, interpreting something you see.”

The arson division chief said when he started at DFD, a more experienced investigator taught newer investigators their techniques and “you just pretty much took it as gospel.”

One technique that has now been debunked is a sheen on water, meaning there was some sort of ignitable and flammable liquid used to start the fire, Richardson said. Another debunked theory is that if mattress springs no longer bounce back from a mattress, it means an accelerant was used.

These arson myths were believed as facts

Syed said there were many myths believed as fact up until the late 1980s, such as that there are physical markers that can prove arson, that melted aluminum under a door sill means the fire was too hot and gas had to have been poured, or that burn patterns on the floor mean accelerants were poured.

“All this through controlled experiments was revealed to be baseless,” Syed said. “Through controlled tests, it became clear some of the stuff they were relying on was unreliable.”

Beginning in 1992, the fire investigation community issued standards for itself. There initially was a lot of pushback, Syed said, as experts were trying to bring science into something not previously seen as a scientific endeavor. The National Fire Protection Association puts out a new edition every few years, updating what methods are seen as the best practices.

The percentage of fires deemed arson has dropped precipitously, Syed said. Even common investigative methods today, such as using accelerant-detection dogs, can come with problems if the guidelines aren’t properly followed, he said.

Any debris that a dog alerts to as having an accelerant on it should be tested in the lab, and if the lab test if negative, the dog’s read should not be allowed to be used in court, Syed said. The dog can’t say why it is alerting, he said, and it could be reacting to something like plastic or foam melting rather than to the presence of an accelerant.

The Michigan State Police is hosting four different sessions of fire investigation training in 2026, according to its website. The program is nationally accredited and is recognized as a leader in fire investigation training, according to MSP.

“The purpose of the program is to provide investigators with a solid foundation of fire investigation skills,” according to MSP’s website. “A variety of methods and resources will be utilized to facilitate learning, including classroom lectures and hands-on training.”

The Detroit Fire Department also hosts one of the state’s two fire investigation trainings twice a year. The course teaches about scientific fire investigations, how to determine the origin and cause of a fire, and how to create policies for fire investigation units in smaller departments.

“Our intent for this class is a basic overview, to give you more experience because a lot of these municipalities don’t have the experience of actually having multiple fire scenes they go to and train at,” DFD’s Richardson said. “Lucky, or unlucky, for us, we can fill that gap there.”

kberg@detroitnews.com