The unbearable heat waves throughout the United States have greatly extended fire season. With this in mind, and based on my relationship with CalFire, Los Angeles County and Ventura County Fire Departments, and the ATF, as well as his experience in several devastating local wildfires and years or research on the subject, I thought it might be interesting to take a behind the scenes look at wildfires arsonists.
What kind of person sets wildfires? What motivates a person to torch the landscape?
First, let's eliminate the motives for the kinds of fires we're not talking about: revenge - a guy's girlfriend breaks up with him. He gets angry and sets her apartment on fire. That's his way of paying her back. Fraud - someone torches his car because he can't make the payments, or maybe he burns down an entire building to collect the insurance on a failing business. Hate Crime - someone sets fire to a church or Synagogue. In these cases, the reason for the fire is relatively easy to understand. The use of fire is the means to an end.
Now consider the more complex case where the fire itself is the objective--we're talking about someone who deliberately sets out to start one or more fires during the worst weather conditions, when the fire is sure to spread and wreak havoc. Most likely, we're talking about a repeat offender, a serial arsonist, what the investigators refer to as a "fire setter." For these arsonists, the forecast of fire weather conditions, or even the report of a massive conflagration, will be an emotional trigger, bringing them out to start their own fires, often several at a time.
Who is the fire setter, and why does he do it? I use the word "he," because arson is predominately a male activity. There aren't many female arsonists. The majority of fire setters are white men between the age of 17 and 25. They are preoccupied with fire and get an emotional release from starting fires. There may be sexual overtones--some researchers claim fire setters are sexually repressed males who masturbate at the fires they set.
The reasons a person becomes a fire setter are complex. Many arsonists are social outcasts who are incapable of stable interpersonal relationships, especially with women. They come from troubled and fragile backgrounds. A dysfunctional or violent family environment is often a contributing factor and the typical fire setter had one or both parents missing from home during his childhood. If his family was intact, he lived in an unstable--often abusive and violent--emotional atmosphere and had a distant and hostile or aggressive relationship with his father. He may suffer from depression, borderline personality disorder, or even suicidal tendencies. Not surprisingly, a large percentage of arsonists indulge in alcohol and drug abuse.
Most investigators will tell you that the fire setter does not think ahead to the possible widespread destruction his arson fire will cause. He's satisfying an immediate need--he's starting fires for the excitement he cannot find elsewhere. Further, it gives him a sense of control over something in his life. For many, firesetting satisfies a desire to be recognized and establishes a sense of self-esteem. For others, setting fires is an act of aggression, which allows them to express anger and frustration. Many arsonists have repressed rage for authority figures. Some get the satisfaction of "getting away with a crime."
Often the preoccupation with fire starts in childhood. A child who is "curious" about fire can grow into an antisocial and aggressive adolescent. Delinquent fire setters are often bored, and starting fires provides them with excitement and stimulation. For many, arson is the beginning of a wide range of activities leading to criminal conduct.
While teen-age arsonists often engage in fire activity with peer groups, by adulthood, most arsonists set fires alone. Psychologists distinguish between two types of adult arsonists: EMOTIONALLY DISORDERED - these are individuals who are emotionally unbalanced and find setting a fire has a calming influence; THOUGHT DISORDERED - these are individuals afflicted with a range of illnesses from learning disabilities to full blown schizophrenic behavior. 
There are not many old arsonists. For unexplained reasons, after the age of 25, most arsonists cease fire setting, but some move on to activities that are more ominous. While doing research for my serial arson mystery novel, I had the opportunity to talk to an arson profiler at the ATF. He told me that serial arsonists often have a history of torturing or killing animals as children, and that some serial killers are serial arsonists when they are younger.
One subset of arsonists bears special mention. "Firefighter-arsonists" sounds like an oxymoron, but they exist. Most are one-time fire setters who are bored at work and want to go out and "fight the fire devil." Then there is John Orr, the infamous California fire captain who is now serving a life sentence for numerous arson fires in which four people died. Law enforcement officials say he was the most prolific arsonist of the 20th Century, possibly responsible for as many as 2,000 fires between 1984 - 1991.
Orr wanted to be a police officer, but was rejected based on his psychological profile. He eventually became a fire captain and arson investigator for the Glendale Fire Department in Southern California. During the '80s and early '90s, there was a series of unsolved arson fires around the Los Angeles area. Orr was often the first on scene and took control of the investigation. 
While there are differences and similarities between many wildfire arsonists, perhaps the most consistent trend is the increase in acts of fire setting during the harshest weather conditions.
1. Michael B. First; Allen J. Frances; Harold Alan Pincus (2004). Dsm-iv Tr Guidebook. American Psychiatric Pub. p. 337. ISBN 978-1-58562-068-5. Retrieved 24 February 2013.
2. Petherick, Wayne (2006). Serial Crime: Theoretical and Practical Issues in Behavioral Profiling. New York, N.Y: Academic Pr