The Fire Condition We Can’t Control For

When a wildfire starts, there is rarely a witness.

Deep in the mountains, lightning strikes a tree on the hottest day in millennia. A dragging trailer chain, unnoticed by a driver, sends sparks into the bone-dry roadside brush. Hikers splash water over an illegal campfire, but it continues to smolder after they leave. And on the right day, in the right weather, unattended and unreported, these fires start to grow.

There is another kind of fire, too — one where the presence of a witness, some would argue, is the entire point. Arson officially accounts for only about 10% of fires handled by Cal Fire, the agency that manages wildfires and structure fires on California’s 31 million acres of wildlands and forests. But when there are thousands of fires across the state during a given season, that’s not an inconsequential number. “Getting 300 to 400 confirmed arson fires a year — that’s a lot of fires that don’t need to occur,” Gianni Muschetto, the staff chief of Cal Fire’s law enforcement division, told me.

The Park Fire, which has burned nearly 400,000 acres near Paradise, north of Sacramento, is now the fourth biggest wildfire in California’s recorded history. As of Friday afternoon, it is still only 24% contained. Investigators have charged 42-year-old Ronnie Dean Stout II with felony arson in connection with starting the blaze, alleging he pushed his burning car into a gully, where it ignited the surrounding vegetation. (Reports conflict over whether Stout set his car on fire intentionally or the engine accidentally caught fire while he was revving it.) Stout was then “seen calmly leaving the area by blending in with the other citizens who were in the area,” Butte County District Attorney Mike Ramsey said in a statement. Stout denies the charges.

In California, which has extremely strict arson laws, the felony is divided in the penal code into two different categories: “reckless” and “intentional” arson. Muschetto explained that someone shooting off illegal fireworks on a dry day might be charged with reckless arson: “They weren’t necessarily trying to start a wildland fire, but because of their reckless act, they did.” On the other hand, if the person shot the fireworks directly into dry grass to purposefully start a fire, “that would be a malicious arson act” and considered intentional. (Investigators had initially planned to charge Stout, the Park Fire suspect, with intentional arson but ultimately charged him on Monday with reckless arson, according to reports.)

Cal Fire lumps reckless and intentional arson together in their public statistics, which show an uptick in arson arrests from 61 in 2018 to over 110 every year since 2020, peaking at 162 in 2022. Muschetto attributes that rise to the fact that fire seasons have gotten longer due to climate change, meaning small acts of arson are more likely to result in fires big enough to warrant resources, investigations, and arrests. In 2023, for example, Cal Fire’s arson arrests dipped slightly, potentially because it wasn’t as long or severe of a fire season in the state.

The 2024 season has kicked off relatively normally, and Muschetto said he expects arson arrests to top 100 but not “break any record number, hopefully.”

The truth, though, is that arson happens “every single day,” Ed Nordskog, a retired Los Angeles arson investigator and the founder of the Serial and Wildland Arson Investigation Training program, told me. “But most of the year, it’s not conducive to a massive fire because of the weather and fuel conditions, so nobody gets excited.” Nordskog disputes reported arson numbers, pointing to the inconsistencies between fire agencies and the lack of resources available to investigate every fire with the thoroughness required to determine its origin. He estimates that closer to 50% of urban and wildland fires are caused by arson, though he agrees that number is likely lower when it comes to wildfires; many experts, however, admit that the commonly cited 10% statistic is probably an undercount.

Nordskog told me that arson investigators don’t care about the size of the fire; they care about the intent of the person who committed the act. Someone like the Park Fire suspect “didn’t have the ability to light a big fire; he didn’t have the ability to light a small fire,” Nordskog said. “He just lit a fire, and he did it on the wrong day, at the wrong time, in the wrong place, and now you have a catastrophe.”

Nordskog is particularly rankled when people try to connect climate change to acts of arson, calling it a misconception that hot weather brings out the firebugs. Arsonists “are there all the time, 24 hours a day, doing their thing,” including in the winter, Nordskog explained. But a warmer world has made extreme fire conditions more common, as have decades of misbegotten fire suppression policies in the Western United States. As a result, arson fires in rural areas are more likely to burn out of control than they would have been half a century ago. That element of chance is why Nordskog likes to say that “a wildland arsonist has the power of a nuclear bomb at their fingertips: They’re the only criminal in the world that can do that kind of damage.”

Most arsonists are one-and-done offenders, and the crime cuts across race, gender, and education levels. Mental illness and drug use can certainly be exacerbating factors. Additionally, the housing crisis and anti-homelessness legislation have pushed marginalized populations into living in wildland-urban interfaces, on the fringes of towns and cities, where both intentional and unintentional fires can cause more extensive problems.

Nordskog specializes in serial arsonists — a much smaller subset of arsonists who set fires repeatedly and intentionally, sometimes hundreds of times. They can be sophisticated operators, picking “the perfect time of day” to start a fire when temperatures are high and the wind picks up; some even use delay ignition devices to avoid getting caught. “They’re usually very frustrated and angry about something,” Nordskog said of a motive, and “the one thing that anybody can do is light a fire.”

Nordskog, like Cal Fire’s Muschetto, told me he’s doubtful there is any significant rise in the number of people actually committing arson; discrepancies in investigations, annual fire conditions, and several other factors are the likelier reason for the fluctuations in numbers.

For Muschetto, though, it defies belief that someone would intentionally start a fire at all. “It blows my mind that [arson] occurs and how often it occurs,” Muschetto told me. An arson fire takes firefighters away from their families for potentially weeks on end; it puts first responders and the public in danger; and between the smoke pollution, immense environmental degradation, and potential loss of life and property, the damage can be incalculable.

“We’re always going to get accidental or natural ignitions” in California, Muschetto said. That’s why “reducing these intentional fires is very important.”

Editor’s note: This story was last update August 2 at 4:30 p.m. ET.