ALTHOUGH THE FIRE service has made great strides in the field of arson investigation, as a whole we have yet to achieve a comparable level of expertise in our approach to arson prosecution. Plain and simple, our role in the legal process of arson justice is a weak link in the chain. We must upgrade the quality of our interaction with court officials and law enforcement organizations, the way we gather and handle evidence, die way we prepare court cases for trial, and the way we testify.

From 1981 to 1983 Abt Associates Inc., a private research company in Cambridge, Massachusetts, conducted a study on the state of arson, funded by the National Institute of Justice. Four cities with varied and diverse arson problems were studied. Data consisted of interviews with arson prosecutors and examination of more than 900 arson fire cases.

Major findings include the following:

  • The conviction rate for the crime of arson is extremely low.
  • Fire investigators don’t put enough emphasis on preparing an effective court presentation, especially in relation to evidence of incendiary origin and motive.
  • Suspects and real leads often are not followed up.
  • Prosecutors don’t involve themselves in arson cases early enough.
  • Arson cases must be extremely strong to be accepted for prosecution.
  • Prosecutors are very inconsistent when screening arson cases.
  • Arson cases accepted for prosecution are usually straightforward and simple.
  • If an arson case is actually accepted and tried, the conviction rate is higher than with other felonies.

Prosecutors are often reluctant to take on arson cases—the low conviction rate for arson makes it a high risk politically. Those that are accepted are usually assigned to an inexperienced district attorney. What’s needed to get more arson cases into the courts for prosecution?


Most district attorneys don’t understand—and have never been given the opportunity to understand —the science of fire investigation. In general, the same is true of fire investigators with regard to the legal aspects of arson. The fire service must take the first steps toward building a mutual understanding and an efficient working relationship:

  1. Present yourself to the attorneys as a competent, educated professional. Change your image if it needs changing. Make it clear that you are willing to work with them.
  2. Demonstrate how your technical education and ability to gather and interpret evidence can help you make sense out of what is to the untrained observer just a pile of fire rubble. You’re not out to teach the legal professional everything you know, but it would certainly help him to have a basic understanding to take the mystery out of what you do. Invite the district attorney to accompany you on a fire scene investigation.
  3. Make yourself available for education on what the district attorney needs to bring an arson case to court. Your objective is not to pass the bar exam but to do everything possible in the interest of arson justice.


Fire investigators must maximize their evidence-securing and -handling skills in order to recreate the crime scene for the jury. The nature of evidence is often misunderstood, but evidence is the only road through which proof is achieved. There are many types of evidence—statements, admissions, testimony, records, papers, photographs and sketches, specimens, and so on.

Arson evidence is usually difficult to gather because it is often hidden, altered, or destroyed. Fire suppression units must be trained to identify possible evidence. They are the first ones on the scene and as such are vital to the successful prosecution of the case. When the investigator arrives on the scene, he should make sure a scan of the crowd is done and a full set of photographs are taken. He must obtain names, addresses, and phone numbers of the witnesses. He should contact the chief officer to receive any pertinent information from him.

Evidence is only valuable as long as it remains admissible in court. The firefighter as well as the fire investigator must prevent any transaction—such as leaving the building unattended—that could compromise the integrity of the evidence.

A crime lab can be invaluable to the fire investigator, but only if the evidence is properly and legally collected and transferred to the lab. The officer in charge of fire suppression crews may have to delay water application to certain areas of the building during overhaul until valuable evidence is collected. Evidence should be collected as soon as possible. Most of it can be placed in common paper bags. Any material that may contain liquid or vapor of a suspicious nature should be labeled and sealed in a clean metal container such as a virgin paint can. Material with hydrocarbon residue should never be placed in a plastic bag or plastic container because the vapors will penetrate the plastic and become undetectable from the sample. Seal evidence with masking tape and use some type of identifying system. When collecting evidence, record what, when, where, and how evidence was found and what will be done with it.

The chain of custody must be maintained and the whereabouts of evidence must be recorded at all times. Anyone breaking the seal on the evidence must document this action and the reason for doing so.

When at the fire scene, note anything unusual such as odors, charring patterns, residues, and devices. Note the state of the building, sprinkler systems, detection, and occupancy. Take photographs liberally. Visual presentations can help the grand jury to see probable cause.

Work together with the crime lab. Let its personnel know how you interpret the evidence—a possible starting point. Remember, however, that lab results can be surprising even to the most experienced fire investigator: On one hand the lab’s technology may not be able to give substance to your suspicions; on the other hand it may be so sophisticated that what you thought was foolproof evidence is useless to the prosecution. Minimize surprises and maximize realistic expectations with a good working knowledge of what the crime lab can and cannot do.


Cooperation between police and fire officials is imperative to the success of any arson prosecution. An investigator who is knowledgeable about origins and causes of arson fires but who has little expertise in criminal investigation and prosecution is at a substantial disadvantage even before appearing before the grand jury. The same is true for the police officer’s understanding of fire investigation. A battle of jurisdictions between police and fire organizations has hurt arson investigations in the past. Fire investigators have “forgotten” to discuss evidence with the local police; police officers have “forgotten” to process evidence collected by fire personnel. It sounds petty and it is, but it has happened, and the community suffers. Clearly, a marriage between the two groups is called for so that each benefits from the other’s expertise. Cross-training may be helpful in this regard.


A key element to successful arson crime prosecution is preparing for the trial. Evidence must be collected. There is also a substantial “paper chase” that must be executed. This hopefully will establish the insurance carrier, previous claims, and any recent changes in the property. A review of the financial condition of the property is also necessary.

Preparation for the prosecutor is essential. The following must be submitted:

  • A fact sheet listing all witnesses and what their testimony will contribute to the case.
  • A narrative report outlining the pertinent details and chain of events from fire scene to date.
  • All substantiation available such as evidence, lab results, statements, photographs, and fire department reports.

The ability to testify in court has become an important part of the fire investigator’s job description. Due to a lack of training, many fire investigators feel uneasy and unqualified when attempting to give testimony. This must be rectified, for courtroom demeanor, attitude, and speech are as important as the content of the testimony. Be prompt, and be aware of your appearance. Dress conservatively, avoiding uniforms if possible. Be courteous, factual, and accurate in your answers, answering only what you’ve been asked. Don’t volunteer information. Be aware of your posture. Make eye contact with the questioner and with the jury.

In order to give testimony in an arson jury trial, the fire investigator usually is required to qualify as an expert witness. Prior to appearing in court the fire investigator should review the case, including fire scene notes, fire company reports, witness interviews, police reports, sketches and photos, and evidence. The district attorney can often render aid to the fire investigator in qualifying as a witness. There are many factors that can help one in qualifying as an expert witness such as experience as a firefighter, fire investigation experience under an experienced fire investigator, the number of previous investigations, employment history, memberships and degrees, and training and simulated burns.

Don’t be riled by the opposition. The defense attorney will aggressively attempt to confuse and discredit the fire investigator. All your courtroom demeanor skills should be drawn on at this time.

There are many defenses to the crime of arson. The fire investigator should be aware of the various avenues of defense available to the defendant. A good alibi can cripple a case, and the accused has only to cause some doubt in the jurists’ minds that he was on the crime scene while the crime was being committed. The importance of scanning the crowd at a fire scene is therefore obvious. Intoxication as a defense is allowed in only a few states. Many states recognize amnesia as a defense, even amnesia that’s self-induced by drugs. Age can be a factor in arson prosecution. In many states, a person under 10 years of age is deemed as not having the capability of criminal intent. Other defenses include suppression of statements, insanity, suppression of evidence, coercion, and entrapment.

We must ask ourselves, in light of what must be an unacceptable national conviction rate for arson criminals, whether or not we are doing everything in our power to improve the situation. It’s clear that fire investigative skills are not enough. We must become educated :n the legal aspects of arson and cooperate with all who work on the case-law enforcement officers, attorneys, witnesses, and all others present at the fire scene.


McGuiness, Pat. “Mounting an Arson Offensive.” Firehouse. August, 1984.

Hammett, Theodore M., Ph.D. “Arson Prosecution: Ingredients for Success.” Firehouse. August, 1985.

Golden, Joan. “Understanding Crime Lab Work.” American Fire Journal, June, 1984.

Kossip, Stanley J. “Courtroom Concerns for the Firefighter.” Fire Engineering. July, 1984.

National Fire Academy Research Project. The Fire Investigator in Court. Emmittsburg, Maryland. July 9-27, 1984.

National Fire Academy Research Project. Evidence—Fire Scene to Court- room. Emittsburg, Maryland. August 1331, 1984.

National Fire Academy Research Project. General Problems Encountered with Prosecutors Accepting Arson Cases for Prosecution and Practical Solutions to Those Problems. Emittsburg, Maryland. October 11-29, 1982.

National Fire Academy Research Project. Defenses to the Crime of Arson. Emittsburg, Maryland. September 13October 1, 1982.

National Fire Academy Research Project. How Would You Prepare an Arson Case for Trial? Emmittsburg, Maryland. October 5-21, 1981.

National Fire Academy Research Project. Law Enforcement I Fire: Cooperative Fire Investigation. Emittsburg, Maryland. August 13-31, 1984.

National Fire Academy Research Project. Fire Investigators and the Media. Emmittsburg, Maryland. May 9-27, 1983.

Summers, Paul. “Don’t Overlook Commonplace Tools When Outfitting Arson Investigator,” American Fire Journal. June, 1984.

No posts to display