SOLEDAD, CALIF. — The evidence seemed overwhelming.
Investigators determined a house fire that killed a woman and two children had been deliberately set. A witness said she had seen George Souliotes, who owned the house and was evicting the tenants, at the scene minutes before flames erupted.
Forensic investigators even matched a flammable substance on Souliotes' shoes to fire debris from the Modesto house.
Thirteen years later, the evidence that convicted the Greek immigrant of triple murder and sent him to prison for life without parole is beginning to unravel.
Although prosecutors say they remain certain that Souliotes set the fire, scientists said investigators concluded the blaze was arson based on assumptions that are now known to be false.
For decades, fire investigators believed accelerant-propelled arsons left signs: melted steel, glass etched by tiny cracks, certain patterns and markings.
But when the theories were finally tested, scientists learned the conditions also were found in accidental blazes.
The turning point for fire science came in 1992 with the publication of a seminal guide by the National Fire Protection Assn.
The report dispelled myths that had guided fire investigations for decades, but years passed before the report's conclusions were embraced.
Even today there are investigators with little training who cling to the old beliefs, according to leading fire experts.
"There is still a pretty sizable rear guard who don't want to admit they were doing it wrong," said John Lentini, a fire scientist who was hired by Souliotes' defense. "It is understandable, because the worst thing you can do is send a person to prison for a crime they did not commit."
The execution of Todd Willingham in Texas in 2004 for the arson murders of his three children haunts many fire experts. Subsequent reviews of the forensic evidence indicated that blaze was probably accidental.
Investigators are so concerned that bad science may have wrongly convicted innocent people that several have agreed to review old cases where the science was wrong and there was little other evidence.
"There is a real sense of insecurity among a lot of people in the field that the Willingham case may represent the tip of the iceberg," said James Doyle, director of the Center for Modern Forensic Practice at New York's John Jay College of Criminal Justice, which is screening the cases.
"You can't help but be nervous given how different the fire science is today from the folklore" that guided probes in the past, he said.
Souliotes' case might have been forgotten if not for his sister, Aleka Pantazis, 63, a Glendale resident whose efforts helped debunk what a prosecutor had called "the most conclusive scientific evidence" of his guilt.
Fire scientists say that arson investigators misinterpreted the evidence at the scene, and a former FBI agent hired by Pantazis found Souliotes was truthful during a polygraph test when he denied setting the blaze.
"She has fought like a lion," Souliotes, 69, said during an interview at Salinas Valley State Prison near Soledad.
The woman's campaign -- aided by friends from St. Sophia's Greek Orthodox Cathedral in Los Angeles -- is now in the hands of the U.S. 9th Circuit Court of Appeals, which will soon decide whether Souliotes should have his case reexamined. He argues that he is innocent and received incompetent legal representation.
Pantazis, whose thick accent and blue eyes match her brother's, has raised money, tracked witnesses, made timelines and reenacted events to try to prove her brother did not set the 1997 fire that killed Michelle Jones, 31, and her children, Daniel Jr., 8, and Amanda, 3.
Pantazis was at home with her family 13 years ago when Souliotes' son called her from Modesto.
Dad is in jail, he told her, and his face is all over the news. Her nephew said he wanted to call earlier, but his father figured the police would quickly realize their mistake and release him, she said.
Pantazis met with her brother the next day. He wore an orange jumpsuit and had tears in his eyes, she said.
" 'Aleka, I don't know why I am here,' " she said he told her.
Souliotes, divorced, managed his rentals and spent his free time traveling to ballroom dance competitions with his girlfriend. The two were planning to visit Greece.
Pantazis sat through Souliotes' two death penalty trials: The first jury hung 11 to 1 for conviction, prosecutors said, and Souliotes said he refused an offer of 15 years to life before the second trial.
An appellate lawyer who suspected Souliotes was innocent called the Northern California Innocence Project, which takes fewer than 1% of the cases it reviews. The Santa Clara University project is now trying to win Souliotes a new trial.
Police and fire records show the house was still smoldering that Jan. 15 when investigators began focusing on Souliotes. The landlord was behind bars by day's end.