Forensic expert
Verified 27 March 2026 - Public Service / Directorate of Legal and Administrative Information (Prime Minister)
The forensic expert is a technician specialized in a particular field. He is appointed by a judge to give his opinion on technical points on which the solution of a dispute depends. There are experts in all subjects (medicine, noise pollution, car accident, building). We present you the information to know.
The judicial expert should not be confused with the amicable expert, who intervenes on the initiative of the parties outside any judicial procedure and does not have the status ofauxiliary of justice.
The forensic expert is a natural person or moral listed by the courts of appeal and the Court of Cassation.
This is a professional who must have recognized technical skills. They must therefore have sufficient know-how, training and professional experience in the specialty concerned.
Likewise, it must also justify personal guarantees, namely:
- No act contrary to honor, probity (honesty/loyalty) or morality
- No disciplinary or administrative sanctions
- No personal bankruptcy or similar penalty.
The choice of the judicial expert is up to the judge. He chooses the person he considers most qualified to intervene.
In principle, only one expert is appointed in order to limit the costs of the procedure. However, the judge may appoint several experts when the complexity of the case so requires, particularly if the facts require the intervention of specialists from different disciplines. This is the case, for example, with medical expertise, analysis of genetic fingerprints or patents.
Request for expertise
The appointment of a judicial expert is, in general, requested by the parties themselves.
One of the parties goes that way refer the matter to the competent court through his lawyer. The request must be reasoned and justified. It is, in fact, mandatory to demonstrate the usefulness of the expert assessment measure, in particular because it enables the court to provide technical clarifications that are essential for deciding the dispute.
The judge orders or refuses this measure.
The judge may also decide, on its own initiative, to appoint an expert. This measure is taken when it considers that the expertise is essential to gather all the necessary elements and make its decision in full knowledge of the facts.
Decision of the judge
If the judge orders the measure of expertise, his decision must contain:
- A statement of the circumstances that make the expertise necessary
- The name of the designated expert(s)
- The mission of the expert
- The period within which the expert must give his opinion.
In principle, the judge calls on experts on lists. Exceptionally, the courts may, by reasoned decision, choose experts not appearing on any of those lists.
Every year, the courts of appeal draw up a list of experts.
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Similarly, the Court of Cassation establishes a national list of experts by specialty.
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The fundamental mission of the judicial expert is to provide technical information that the judge does not have, to help him decide the dispute.
In practice, the judicial expert is responsible for:
- Determine the plausibility (substantiation) of a technical or scientific claim (assertion) raised by a party to the trial
- Advise on the cost of an operation, damage or repair
- Provide objective and impartial advice on a technical, scientific, economic, accounting, medical, etc. matter of fact, depending on the specialty required by the dispute.
On the other hand, it is forbidden to give legal assessments.
FYI
The forensic expert provides a technical opinion to inform the judge. This opinion, however, has only one advisory value : the judge remains free to follow this opinion or not to decide the dispute.
The judicial expert may also be entrusted with a conciliation parts. In this case, he will have to accompany the parties to find an amicable solution to their dispute.
It will listen to the arguments of each party in an impartial manner, promote dialog and seek common ground.
The forensic expert must respect several obligations essential to the performance of its tasks, namely:
- Respect for the adversarial principle : all parties must be informed of and able to participate in expert appraisal operations. The expert must provide the parties with all the documents on which he will base his report, so that everyone can read it and submit his observations.
- Independence and impartiality : the expert must act objectively and not favor any party. He must refuse any assignment if there is a conflict of interest and declare it immediately to the judge.
- Conscience and probity : the expert must carry out his mission with rigor, honesty and neutrality, providing sincere and detailed technical advice.
- Professional secrecy : the expert shall be bound by confidentiality with regard to information that comes to his or her knowledge in the course of his or her mission.
The remuneration of the judicial expert shall be fixed by the judge at the end of his mission.
It takes into account several criteria, including:
- The due diligence accomplished
- Compliance with the deadline for completing the mission
- And the quality of the work provided.
The judge is not bound by the amount requested by the expert or by the observations of the parties. He decide independently on the basis of the information in the file and any written observations made by the parties.
Please note
The remuneration of experts is included in the cost of the trial, it is part of the costs.
During the mission, a provision to be applied to remuneration is generally paid by the party or parties designated by the judge. In practice, the order appointing the judicial expert sets the amount of 1era provision and specifies the party who is to pay for it. In the majority of cases, this burden is borne by the party requesting the expert assessment, which thus assumes the initial payment.
At the end of the judicial expert's report, the judge orders either the payment of additional sums or the return of the sums deposited in excess (in excess). It shall also specify the party or parties responsible for it. This cost is, in principle, borne by the party who lost the case.
FYI
The remuneration of the judicial expert may be covered by legal aid if the losing party meets the conditions to benefit from it.
Once the expertise is ordered, a judge is responsible for reviewing expert opinions. Its role is to supervise the mission entrusted to the judicial expert in order to guarantee its smooth running, the protection of the rights of the parties and the conformity of the expert appraisal operations with the mission defined by the court.
The expert must thus keep the judge informed of the progress of his operations and the diligences accomplished. It also informs the Committee of the difficulties it encounters in carrying out its mission. Similarly, if the mission is to be extended, the judicial expert must request it so that the judge can authorize an additional period.
The parties may also refer the matter to the judge responsible for reviewing the expert appraisals in the event of a problem (delay, failure of the expert to fulfill his mission, lack of response, etc.).
The compliance with ethical rules the judicial expert shall also be subject to specific supervision by the following authorities:
- First President and Attorney General of the Court of Appeal, for experts on the lists of the courts of appeal
- First President and Attorney General at the Court of Cassation, for experts on the national list.
This control shall include the probity, honor and independence of the expert. For example, it may be used in the event of a serious breach, such as a deliberately altered (distorted) report or a breach of the principles of impartiality.
Yes, it is possible to engage the responsibility of a forensic expert. His liability may be civil, criminal or disciplinary.
Civil liability
In civil matters, in order to hold the judicial expert liable, three cumulative conditions must be met, namely:
- A mistake: it is an error or negligence that a normally astute, conscientious and attentive expert would not have committed. The fault is often technical (error in the analysis, omission, lack of diligence, etc.), or procedural (disregard of the principle of contradiction, non-respect of impartiality, etc.)
- Injury: financial, material or moral damage
- A causal link: the expert's fault must have a direct link with the damage suffered.
Criminal liability
The judicial expert may also be held criminally liable for the commission of an offense (corruption, forgery, breach of professional secrecy, etc.).
Disciplinary responsibility
Finally, the judicial expert may be held liable for disciplinary action in the event of a breach of his ethical obligations.
There is no official title of “judicial expert”. In practice, a judge may designate any natural or legal person with the necessary skills to answer a technical question on which the resolution of a dispute depends.
However, to assist judges in the search for technicians, lists of experts classified by specialty have been established. The courts will find specialists who will be able to assist them in the cases they have to judge.
Inclusion on these lists is subject to several conditions, including professional competence, experience, morality and independence.

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