Arson Investigation in Wildland Fires
Kurt Kamm
July 03, 2008
Imagine an arson investigator arriving at a wildland fire which has already burned 100 acres. He has to determine whether it was an incendiary (intentional) fire, and if so, where and how it was started. This is not like walking into a building where arson is suspected. A building has a limited space, with interior walls, and if it was an arson fire, somewhere within those walls, or right outside, burn indicators and evidence will be found. In the wildland, there is a lot of acreage to cover.
Arson investigators immediately talk to the first responders and seek out any witnesses. These are the people who can give critical information. The first responders may have a good idea where the fire started. Witnesses may have seen someone suspicious. (Note that a normal spectator will run away from a fire. An arsonist often is seen running TOWARD the fire, and often stays around to see the results of his work.) Next, the investigators will try to eliminate causes such as lightning strikes, downed power lines and transformers, passing vehicles, construction work, campfires, or any other activity which might have generated a spark or a flame. Assuming nothing obvious turns up, the painstaking, detailed effort begins, searching for the work of a fire setter.
Fire burns according to scientific principles. A fire will leave physical evidence of its passage which can be identified. Experienced investigators see things in a burnt landscape which are not obvious to the untrained eye. Investigators try to work toward the source of a fire. A full-fledged wildland fire may have flame lengths 50 - 100 feet high, but when a fire starts, it is a small flame which smolders and burns along the ground until it gains force. The difference in flame size and heat can be seen after a fire passes through. Investigators work backward, from the area of most intense burning to the place where the fire began.
A wildland arson investigation is a search for the indicators which show the direction from which a fire has come. Grass, plants, pine needles and leaves will often freeze in a particular direction when a fire hits ("foliage freeze"). Trees, telephone poles and other flammable objects will often show soot and/or more significant burn marks on a particular side, again showing the direction of the fire ("alligatoring"). Rocks may show chips on the side exposed to fire and heat ("spalling"). A fire will burn in a pattern. If there has been no significant wind, it may burn outward in a circle. If wind is present, the fire may burn in a U or V pattern. A strong Santa Ana, or other wind continually blowing in a particular direction, makes it easier to work backward to the origin.
With luck, investigators may be able to narrow the point of origin down to an acre or less. One problem is that unsuspecting fire crews may destroy evidence at the point of origin during their efforts to extinguish the fire. As soon as the approximate area of the origin is identified, investigators will tie off as much as an acre with plastic tape and flags. Law enforcement personnel may be enlisted to keep the area secure while the search for evidence continues.
The final step is to isolate an area, possibly as much as an acre, secure it with "fire scene" tape and try to identify the actual source of the fire. Since most wildland fires start with low intensity and burn outward, once the origin area is identified, the trick is to find the ignition source. If other factors are eliminated (lightning, sparks from equipment, power lines, campfire), the investigators will be searching for a DEVICE, possibly as small as a book of matches taped around a cigarette. Often part or all this device will survive the fire. Investigators will look for a SIGNATURE, that is, a device similar to something used previously. They may tape an area off into three-foot wide lanes, and move very slowly, looking at each square foot with binoculars. It will be slow and painstaking work, going through partially burnt foliage, debris, and ashes. It may be like an archaeological dig, with investigators on their hands and knees, carefully crawling along the ground. Footprints and/or tire tracks may be preserved in plaster, and matches, flares, timers, batteries and other components for an incendiary device are often discovered. Fingerprints and DNA may actually be obtained. Whatever the analysis of the cause of the fire, and whatever evidence is collected, it must all stand up in a court of law if a conviction is to be obtained.
It has been said that, "It takes a special breed of detective to uncover arson. He's part fireman and part cop, with a special understanding of fire science and the criminal mind." (Nova, Hunt for the Serial Arsonist) Most arson investigators have formal law enforcement training. They carry weapons and are regarded as law enforcement officers. CalFire, responsible for investigating fires on California state land, has over 100 arson officers. California is very aggressive in pursuing wildland arson as a result of the heavy financial losses incurred in such fires. The county fire departments in California also have arson and fire investigation units, as well as many cities and towns. Such groups as the San Gabriel Valley Arson Task Force, which is made up of several cities and towns in Southern California, pool their efforts and personnel. It is interesting to note that this particular task force was originally organized by the infamous John Orr, the Glendale, CA fire captain and arson investigator who is serving a life sentence for numerous arson fires in which four people died. Law enforcement officials believe Orr was the most prolific arsonist of the 20th Century, possibly responsible for as many as 2,000 fires between 1984 - 1991.
Additional investigative support comes from the Bureau of Alcohol, Tobacco and Firearms. The ATF has the mandate to investigate all church fires in the US, and provides Certified Fire Investigators to assist in the legal and technical investigations of arson fires and to provide expert witnesses. In California, once fire investigators determine that arson has been committed, the Sheriff's bomb and arson unit may take over the investigation. Fire department investigators tend to have specific expertise in analyzing wildland arson and work closely with the Sheriff's Department. In the case of the Malibu Corral Fire in 2007, set by a group partying in a cave during a red flag warning and caused $450 million damage, the investigation was a joint effort by LA County Sheriff's Department, CalFire and LA County Fire Department. The individuals were caught after investigators traced a credit card receipt for firewood from a local supermarket.
Copyright 2008 – Kurt Kamm
Kurt Kamm writes novels about fires and firefighters. A resident of Malibu, he has lived through several wildland fires. He is a regular visitor at the fire camps, stations and training academies of L.A. County Fire Department and CalFire. To learn more about his novels, One Foot in the Black, and Red Flag Warning, visit http://www.kurtkamm.com.
Arson investigators immediately talk to the first responders and seek out any witnesses. These are the people who can give critical information. The first responders may have a good idea where the fire started. Witnesses may have seen someone suspicious. (Note that a normal spectator will run away from a fire. An arsonist often is seen running TOWARD the fire, and often stays around to see the results of his work.) Next, the investigators will try to eliminate causes such as lightning strikes, downed power lines and transformers, passing vehicles, construction work, campfires, or any other activity which might have generated a spark or a flame. Assuming nothing obvious turns up, the painstaking, detailed effort begins, searching for the work of a fire setter.
Fire burns according to scientific principles. A fire will leave physical evidence of its passage which can be identified. Experienced investigators see things in a burnt landscape which are not obvious to the untrained eye. Investigators try to work toward the source of a fire. A full-fledged wildland fire may have flame lengths 50 - 100 feet high, but when a fire starts, it is a small flame which smolders and burns along the ground until it gains force. The difference in flame size and heat can be seen after a fire passes through. Investigators work backward, from the area of most intense burning to the place where the fire began.
A wildland arson investigation is a search for the indicators which show the direction from which a fire has come. Grass, plants, pine needles and leaves will often freeze in a particular direction when a fire hits ("foliage freeze"). Trees, telephone poles and other flammable objects will often show soot and/or more significant burn marks on a particular side, again showing the direction of the fire ("alligatoring"). Rocks may show chips on the side exposed to fire and heat ("spalling"). A fire will burn in a pattern. If there has been no significant wind, it may burn outward in a circle. If wind is present, the fire may burn in a U or V pattern. A strong Santa Ana, or other wind continually blowing in a particular direction, makes it easier to work backward to the origin.
With luck, investigators may be able to narrow the point of origin down to an acre or less. One problem is that unsuspecting fire crews may destroy evidence at the point of origin during their efforts to extinguish the fire. As soon as the approximate area of the origin is identified, investigators will tie off as much as an acre with plastic tape and flags. Law enforcement personnel may be enlisted to keep the area secure while the search for evidence continues.
The final step is to isolate an area, possibly as much as an acre, secure it with "fire scene" tape and try to identify the actual source of the fire. Since most wildland fires start with low intensity and burn outward, once the origin area is identified, the trick is to find the ignition source. If other factors are eliminated (lightning, sparks from equipment, power lines, campfire), the investigators will be searching for a DEVICE, possibly as small as a book of matches taped around a cigarette. Often part or all this device will survive the fire. Investigators will look for a SIGNATURE, that is, a device similar to something used previously. They may tape an area off into three-foot wide lanes, and move very slowly, looking at each square foot with binoculars. It will be slow and painstaking work, going through partially burnt foliage, debris, and ashes. It may be like an archaeological dig, with investigators on their hands and knees, carefully crawling along the ground. Footprints and/or tire tracks may be preserved in plaster, and matches, flares, timers, batteries and other components for an incendiary device are often discovered. Fingerprints and DNA may actually be obtained. Whatever the analysis of the cause of the fire, and whatever evidence is collected, it must all stand up in a court of law if a conviction is to be obtained.
It has been said that, "It takes a special breed of detective to uncover arson. He's part fireman and part cop, with a special understanding of fire science and the criminal mind." (Nova, Hunt for the Serial Arsonist) Most arson investigators have formal law enforcement training. They carry weapons and are regarded as law enforcement officers. CalFire, responsible for investigating fires on California state land, has over 100 arson officers. California is very aggressive in pursuing wildland arson as a result of the heavy financial losses incurred in such fires. The county fire departments in California also have arson and fire investigation units, as well as many cities and towns. Such groups as the San Gabriel Valley Arson Task Force, which is made up of several cities and towns in Southern California, pool their efforts and personnel. It is interesting to note that this particular task force was originally organized by the infamous John Orr, the Glendale, CA fire captain and arson investigator who is serving a life sentence for numerous arson fires in which four people died. Law enforcement officials believe Orr was the most prolific arsonist of the 20th Century, possibly responsible for as many as 2,000 fires between 1984 - 1991.
Additional investigative support comes from the Bureau of Alcohol, Tobacco and Firearms. The ATF has the mandate to investigate all church fires in the US, and provides Certified Fire Investigators to assist in the legal and technical investigations of arson fires and to provide expert witnesses. In California, once fire investigators determine that arson has been committed, the Sheriff's bomb and arson unit may take over the investigation. Fire department investigators tend to have specific expertise in analyzing wildland arson and work closely with the Sheriff's Department. In the case of the Malibu Corral Fire in 2007, set by a group partying in a cave during a red flag warning and caused $450 million damage, the investigation was a joint effort by LA County Sheriff's Department, CalFire and LA County Fire Department. The individuals were caught after investigators traced a credit card receipt for firewood from a local supermarket.
Copyright 2008 – Kurt Kamm
Kurt Kamm writes novels about fires and firefighters. A resident of Malibu, he has lived through several wildland fires. He is a regular visitor at the fire camps, stations and training academies of L.A. County Fire Department and CalFire. To learn more about his novels, One Foot in the Black, and Red Flag Warning, visit http://www.kurtkamm.com.