Arson allegations: danger and the role of expert evidence

The description of the offense determines what must be proven

Article 157 of the Criminal Code distinguishes between intentional arson with different dangerous consequences. Article 158 concerns another entry, in which fire due to negligence is central. These descriptions may not be replaced solely by the general word fire. Ask what exactly has been charged and which part is disputed. Intentionally causing fire, the danger and the link to the suspect are not interchangeable facts. An accusation about participation or an attempt also requires its own legal assessment of the conduct in the file.

Therefore, do not start with the largest damage photo, but with the questions that the indictment raises. What would the suspect have done, which shows that, what does the investigation say about the cause and what danger is mentioned? A conflict or financial reason may provide context, but is not independent technical evidence of ignition. Conversely, a technical conclusion about human causation cannot determine which person was responsible. A good defense allows these connections to be examined separately and prevents a plausible general storyline from unknowingly replacing missing links.

What a fire investigation does and does not determine

The NFI describes fire and technical investigation as research into, among other things, origins, development, possible causes and expansion. Traces, devices, documentation and other data may be relevant for this. The researcher must make clear what has been observed and what conclusion follows from it. A report in which a cause could not be established says something different than a report in which a specific cause has been convincingly demonstrated. Read the precise wording and have it explained what a probability or constraint used means for the question being examined. (NFI describes fire and technical investigations)

Our analysis is that legal misunderstandings often arise with that language. Not excluded is read as probable, and probable is then summarized as proven. Those are separate steps. Therefore, write down the question, findings and limitation for each conclusion. Ask an expert for explanation where necessary, without coming up with a scientific scale yourself. The same applies to exclusion of alternatives. If one technical possibility becomes less plausible, it does not automatically follow that every other part of the criminal accusation is established. The remaining conclusion must be based on the totality of the data.

The investigated location and samples require a verifiable origin

In the event of a fire, material can change due to fire, extinguishing, collapse and later clean-up. This makes the documentation of the site, collection and research relevant. Ask which samples or devices were actually examined and where they came from. A missing detail does not automatically prove that research is flawed, but it can raise a specific question about the interpretation. Place the chain from collection to reporting next to the map and photos. This makes it visible whether a conclusion about one place or object is later presented too broadly.

Do not search the location yourself or take materials with you to collect evidence if this affects safety, access or research. Discuss with the lawyer how existing material can be secured and whether additional expert research is possible and useful. Save your own existing photos in their original form and record what they show without filling in any missing details. A reconstruction made later must remain recognizable as a reconstruction. This prevents preparatory material from appearing to provide more certainty about the situation during the fire than it can actually support.

A substance found does not answer every question of guilt

The NFI describes chemical fire research as a separate research area with its own possibilities. A finding about material should be placed with the location, sample examined, and question asked. The presence of a certain substance does not automatically tell who brought it there or for what purpose. Nor can it be assumed without expert explanation that absence in one sample rules out every conceivable act of arson. It concerns what was investigated in this case and what can be responsibly deduced from that result.

Keep different layers of information next to each other. The laboratory finding is one layer, the statement about normal use or previous presence another and the legal conclusion another. Have an alternative explanation fit in with existing data and let the researcher assess whether it is technically relevant. A loose general possibility does not refute every finding. Conversely, an unknown background should not be filled with a firm accusation. The core of a good question is: what distinction can the available track actually help make between the concrete scenarios examined?

A technically explained fire does not itself link itself to a person

The link to a suspect can be made from statements, images, communication, presence or other data. Ask for each piece of information what it really says. Being at a location is different from performing the proven act. An incriminating message may be important, but it should be read in full and in context. The ability to access a property does not automatically prove exclusive access. The Public Prosecution Service can use various indications together; the defense must therefore be able to control both the individual sources and the step towards their joint meaning.

Create a timeline distinguishing between observation and inference. Who saw what, at what time and under what circumstances? In the event of a fire, people can understandably mainly remember the emergency situation and reconstruct approximate times later. A deviation is not immediately a conscious untruth, but it can have significance for the stated order. Ask specifically for underlying data when an exact time seems relevant. A statement that only emerged after inspection of other information should not be presented as an original independent observation without explanation.

Danger to be feared is a separate legal element

Various variants of Article 157 concern common danger to property, danger to life or danger of serious bodily injury, with further legal distinctions. Investigate which variant is actually blamed. The severity of the visible damage does not replace proof of that part. Ask about the specific environment, presence of people, structural situation and the fire development on which the danger conclusion is based. An expert can describe technical risks, while the judge assesses whether the legal meaning in the file is sufficiently supported.

That distinction works both ways. The fact that no one was injured does not automatically mean that there was no danger. A timely evacuation or intervention could have prevented consequences. At the same time, the existence of a home does not make a legal conclusion about danger to life self-evident without further substantiation. The relevant moment and the concrete circumstances must be assessed. Therefore, describe not only what ultimately happened, but also what factual basis the hazard assessment has. A happy outcome in retrospect and a risk that could be foreseen in advance are different topics that must remain recognizable in the motivation.

The Supreme Court required proof of the specific danger to life

In ECLI:NL:HR:2009:BG1653 it concerned a fire in a commercial building with an upstairs apartment. The Supreme Court ruled that a danger to the lives of the aforementioned residents could not simply be deduced from the evidence used, because it did not reveal their presence at the time. The judgment emphasizes the foreseeability required at the relevant time according to general rules of experience. The Supreme Court overturned part of the decision and dismissed the case. That is not a general acquittal for every fire where residents happened not to be at home.

The useful lesson is that the danger component must be linked to concrete facts and the right people. The judgment also states that it is not decisive whether the perpetrator himself actually anticipated the intended danger. Therefore, do not confuse the objective assessment of the danger to be feared with separate proof that the suspect had everything in mind. Let the lawyer explain the requirements for each component. In this way, the defense prevents both an overly broad assumption of danger and a defense that focuses on the wrong legal question.

Fictional example: two possible causes and one uncertain link

In a fictional example, a fire breaks out in a workshop. The file contains a technical report, photos and a message from Fenna after a business conflict. A brief summary calls the fire intentional and points out the message. However, the lawyer first reads what the report says about cause and alternatives and which questions remain unanswered. It is then examined what the message really means and whether other data link Fenna to the stated action. The conflict is not ignored, but it does not replace the investigation into cause and involvement.

For a specific question, the locations of material and the timeline of its presence are also compared. Perhaps additional research will confirm the suspicion; perhaps a conclusion turns out to be too firm. The fictional example does not predict an outcome and contains no technical instruction for causing a fire. It shows that careful reading starts earlier than designing your own alternative fire theory. The defense can first ask what conclusions the existing documents support and where an additional source or expert is needed to actually investigate a decisive uncertainty.

Seven fields for reading the technical file

Create a line for each supporting conclusion and keep the original formulation available. Do not immediately write your own preferred outcome in the facts column. An uncertainty remains an uncertainty until research or other data clarify its meaning. Add a separate question for what needs to be additionally investigated and why that counts for the accusation. This map helps the lawyer connect the technical and legal disciplines, without a suspect having to feign expertise or completely refute a large report without delineation.

• Accusation: legal variant, alleged act, intent and mentioned danger element.
• Research question: which cause, extension or material finding is exactly being investigated?
• Source material: location, documentation, samples, photos and any limitations of available material.
• Conclusion: exact scope, distinct scenarios and uncertainties mentioned by the expert.
• Involvement: Which individual data links the technical event to this person?
• Danger: for which goods or persons, at what time and based on which concrete facts?
• Follow-up: targeted question, appropriate expert research and importance for the legal assessment.

Technical certainty must match the legal conclusion

Our conclusion is that an arson file not only requires expertise, but clarity about its boundaries. A technical investigation can be an important link, while the step towards intent, involvement and danger requires its own proof. A good defense makes those boundaries visible and remains open to investigation that can also have an unfavorable outcome. This is substantively stronger than general distrust in every report or automatically presenting a fire without a clear cause as an innocent accident. The conclusion must fit the data that actually support it.

Discuss the original documents through the explanation of the criminal file and determine in a timely manner which investigation questions are still required. In the event of a possible omission, the question of exclusion of evidence must be assessed separately from the technical reliability. The practical map supports the consultation and does not replace an expert report. Above all, it helps to make the decisive connections verifiable: how did the fire start, what did this person do and what danger follows according to the law from the concretely established circumstances? (criminal file · evidence exclusion)