What are full defenses in criminal law

Jurisprudence (hrr-strafrecht.de)

Editor: Rocco Beck

Suggested citation: BGH, 2 StR 221/94, judgment v. August 2nd, 1995, HRRS database, margin no. X

BGH 2 StR 221/94 - judgment of August 2, 1995 (LG Frankfurt / Main)

BGHSt 41, 206; Rejection of an expert because of fear of bias; Negligent assault; Determination of the causal connection (causality) between chemical substances (wood preservatives) and damage to health; free evaluation of evidence (formation of convictions).

Before § 13 StGB; Section 74 of the Code of Criminal Procedure; § 24 StPO; Section 223 of the Criminal Code; Section 230 of the Criminal Code

Guiding principles

1. Requirements for the establishment of a causal relationship between chemical substances and damage to health. (BGHSt)

2. Even if there is no agreement among natural scientists as to whether and in what way poisons cause damage to health, the judge can, based on an assessment of all relevant evidence and scientific opinions, come to the conclusion that they have caused damage to health. In the case of wood preservative exposure, for example, a causal relationship cannot only be demonstrated by either scientifically demonstrating the effects of the wood preservative ingredients on the human organism or by listing and excluding all other possible causes of a disease. Rather, other causes can also be excluded - without their full discussion - by determining beyond doubt the - at least - contributory cause of the wood preservative after an overall assessment of the scientific findings and other circumstantial facts. (Editor)

Decision tenor

On the appeals of the defendants, the judgment of the Regional Court of Frankfurt am Main of May 25, 1993 with the findings is overturned.

The matter is referred back to another criminal division of the regional court for a new hearing and decision, including on the costs of the appeal.

The public prosecutor's revision of the aforementioned judgment is rejected.

The cost of this appeal and the necessary expenses incurred by the defendant as a result of the appeal are borne by the state treasury.



The district court has sentenced the accused for negligent bodily harm in the act of negligent release of poisons to imprisonment of one year each and suspended their execution on probation. Both the defendants and the public prosecutor's office have appealed against this judgment.

The defendants' appeal is successful, the public prosecutor's appeal is unfounded.


The defendant S. was the technical director of company D from October 12, 1972 to April 1, 1987. The defendant H. has been the commercial director of this company since April 1, 1977. This dealt essentially with the manufacture and sale of wood preservatives. These products initially contained the biocidal ingredients pentachlorophenol (PCP) and lindane.

The district court has gained the conviction that wood preservatives which the defendants put on the market after January 1, 1978 (for example Xyladecor 200 with the active ingredient lindane) or which they had already placed on the market beforehand and their use in indoor areas did not prevent them ( Xyladecor with the active ingredient PCP and lindane) 29 people have suffered physical damage.

After hearing various experts, the regional court established a causal connection between the biocidal ingredients of the wood preservatives and the damage to health and explained it as follows:

The toxic substances would be subject to outgassing in the sense of dynamic post-diffusion for years due to the vapor pressure attached to them. After indoor use, the residents are exposed to constant pollution in the low dose range. The outgassing toxins would primarily be absorbed by inhalation via room air and dust particles, cutaneously via the textiles worn and orally via secondary contamination of the food. They would accumulate in the body in considerable quantities and be deposited in the lipid deposits there. Lindane and PCP are so-called lipophilic substances that do not damage a primary target organ, but are deposited in almost all of the organism's fatty distribution areas. In addition to the actual fat tissue, fat-like tissues such as the brain, the central and peripheral nervous systems are also affected. The substances changed the cell structures in the entire organism. They also get into the cell membrane, since fat-like or lipophilic components are present there. The enzymes responsible for metabolism are inhibited and cell activity is reduced. PCP also leads to a breakdown of cell respiration and thus the energy supply of the affected cells.

The mentioned effects would be intensified by the body's own detoxification processes. For the excretion of toxins, the organism provides a specific foreign metabolism that converts the toxins into water-soluble substances. The first phase of the detoxification process, which runs in two stages, serves to increase the reactivity of the foreign substances, whereby their toxicity often increases. It is only in a second phase that the actual detoxification takes place. While a substance that is ingested orally via the gastrointestinal tract is converted into excretable products in the liver without any significant diffusion into the tissue and is then excreted immediately, the toxic active substances administered by inhalation and cutaneous migrate to the liver without prior passage Lungs and heart chambers first in the brain. This leads to the fact that the substances are distributed over the entire organism, remain in their original form for a long time and thus develop their impairing effect. The toxic loads caused disregulation of the immune system. There are defects in the "T cells", the central instruments of the immune system. The immunosuppressive effect of the poisons offers a comprehensible explanation horizon for the sometimes serious, recurring infections in the victims. The multitude of other symptoms of illness, in particular general complaints, endocrinological and neural damage, are explained by the fact that the toxins unfold their cell-damaging effect in the entire organism in the way shown. The fact that neural damage persists despite the end of exposure is based on the fact that damaged nerve cells cannot be renewed.

The criminal chamber relies on the following evidence to prove a causal connection between exposure to wood preservatives and damage to health - just like the experts questioned on the individual cases:

a) The diseases occurred in the residents of houses in which the wood preservative had been applied to a considerable extent indoors.

b) Before using the wood preservatives and before moving into the apartments, the injured parties were healthy.

c) The first impairments occurred as soon as the wood preservative was applied and immediately after moving in. In the first phase these were conjunctivitis, disorders in the ear, nose and throat area, delayed wound healing, skin changes, diarrhea, constant malaise and headaches. With continued long-term exposure, systemic damage has occurred over the years. The immune system as well as endocrinological and neurovegetative functions were affected. Those affected repeatedly suffered from bacterial and viral diseases as well as from general lack of drive and performance, combined with neural disorders, which manifested themselves among other things in memory, language flow and word finding disorders. The health impairments particularly affected children between the ages of 2 and 8 who had been exposed to the effects of the wood preservative since they were born.

d) After moving out of the living rooms treated with wood preservatives or after removing the wood preservatives, there was soon a clear improvement in the general condition of the injured party. The general health then improved. However, the neural disorders regularly persisted. If the wood preservative was only partially or insufficiently removed, there was no improvement in the same way. Renovating the rooms also had a noticeably positive effect on pets and plants that had previously suffered from the outgassing of wood preservatives.

III. Revision of the defendants

The defendants' appeals are successful with a procedural objection. The contested judgment also suffers from a factual and legal deficiency, which must also lead to the judgment being overturned:

1. Notice of procedure

The appeal on appeal rightly objects to the rejection of a request with which the defendants referred the expert Prof. Dr. Hu. have refused because of concerns of bias.

In the main hearing on July 22, 1992, the defendants rejected this expert and justified their request, among other things, with the fact that the expert had expressed in a letter to the public prosecutor dated August 10, 1990 that he was "concerned" that the proceedings against the defendants were involved Decision of July 20, 1990 had not been opened. In this letter, the expert encouraged the public prosecutor to continue the investigation. The above letter has the following wording:

... I learned through the press that the indictment against the managing directors against the two market-leading manufacturers for toxic substances in wood preservatives has failed and the opening of the main proceedings has been rejected. This - so in the Frankfurter Rundschau of August 3, 1990 - with the reason: "According to the current state of knowledge about serious health disorders caused by wood preservatives with biocidal substances, no conviction for bodily harm is to be expected." Out of my professional concern, I would like to expressly encourage you not to give up on this procedure. From my clinical observations of more than 80 wood preservative victims in the meantime, I cannot understand the reasoning of the court in any way. Rather, I would like to send you a letter to the editor written by Professor G. and myself, as of 4/90, and, if you wish, also offer you my further professional help.

The regional court rejected the applications for rejection against the expert and stated, among other things, in this decision:

The letter, from a time before the appointment as a judicial expert, lacks respect for judicial decisions that do not correspond to one's own opinion. It contained a disregard of the decision of the chamber, which the expert was apparently not fully aware of at the time.

Although the subjective view of the accused is understandable, the expert advises not to give up on the proceedings that concern them. From the point of view of a reasonable defendant, however, this does not give rise to a reason for rejection. An objective assessment could not give the impression that the expert was interested in convicting the accused because of some kind of prejudice.

The rejection of the rejection request by the court is flawed in law.

According to Section 74 (1) sentence 1 StPO, an expert can be refused for the same reasons that entitle a judge to refuse. This equality already shows that high demands must be placed on the impartiality of an expert. An expert's report can be of decisive importance for the process.

The expert who has a special, not generally available knowledge in his field and is supposed to support the court with the investigation of the truth in the case to be decided - like the judge - is expected to carry out the task incumbent on him impartially. That is why he - like the judge - can be rejected if there is a reason suitable to justify mistrust with regard to his impartiality.

As a rule, such a reason does not exist if the expert expresses himself in general on a question from his field of expertise in the course of his professional activity, for example in publications, at courses or at specialist conferences, or if he takes a special position on this in the context of the submission of an expert opinion. Statements made within this framework do not in principle justify the concern of his bias, even if the expert may represent a scientific opinion that would be detrimental to the defendant in pending criminal proceedings.

The situation is different, however, where the expert takes an initiative outside the framework described, with which he criticizes a decision that is favorable to the accused and seeks to amend it.

The principles of the revision procedure apply to the examination of the question of whether the judge has rejected an application for rejection against an expert without any legal errors. However, assessing whether a given fact gives rise to bias concerns from the standpoint of a reasonable defendant is a matter of law. The judge is not given any discretion to be observed by the appellate court (see BGHSt 8, 226 f).

In the present proceedings, the expert not only criticized the decision of the regional court, but also expressly "encouraged" the public prosecutor's office to continue the proceedings against the accused and also offered his help in this regard. In doing so, he gave the impression of partiality - even for a sensible defendant. It is irrelevant whether he was interested in convicting the accused or whether he was only anxious to assert his scientific knowledge in the criminal proceedings. The decisive factor is that the defendants must have had the impression that the expert was pursuing their conviction and was therefore no longer open in his judgment.

In its decision, with which it rejected the defendant's petition for bias, the district court described the defendant's "subjective view" of the expert's bias as "understandable". If it then comes to the conclusion that from the point of view of a "reasonable" accused there is no reason for rejection and "with objective assessment" the impression cannot arise that the expert is interested in convicting the accused, then this reasoning is contradictory and is based on a legally incorrect understanding of the requirements of §§ 74, 24 StPO.

The contested judgment can be based on the incorrect rejection of the request for bias. When assessing the question of whether the injuries suffered by the injured party can generally be traced back to the wood preservatives from company D. used in the living spaces, the regional court relies on the statements made by expert Prof. Dr. Hu. on the effects of exposure to wood preservatives on the immune system. In addition, the expert Prof. Dr. Hu. in individual expert reports affirmed a causal connection between exposure to wood preservatives and the illnesses for 16 victims.

2. Complaint

With the factual complaint, the defendants primarily object to the assessment of the evidence on the general mode of action of the biocidal ingredients of wood preservatives.

They complain that the findings of the regional court on this point contradict established scientific empirical data. At least in the area of ​​poison exposure in the low dose range, a concrete effect relationship between the biocidal ingredients of the wood preservatives and the health disorders summarized under the term "wood preservative syndrome" has not been scientifically clarified, let alone proven.

What the regional court, citing the expert Prof. Dr. W. and Prof. Dr. Hu. I found out about the effects of the biocidal ingredients of the wood preservatives on cell function when exposed to low doses, is not only accepted in this form by any recognized scientist in the fields of toxicology and immunology, but also goes against the established knowledge of these sciences. If it is a question of clarifying the legalities of the natural sciences, the personal conviction of the judge has to recede even if the relevant questions have not yet been finally clarified by natural sciences. Just as it is recognized in the case law that established scientific empirical sets have a probative value that excludes any counter-evidence in individual cases and any opposing judicial evidence assessment, no matter how unexplained a research subject in the natural science concerned is, that it is "non liquet" for the criminal judge must apply.

The substantive complaint is justified in the result.

The Senate does not have to decide whether the regional court has relied on experts who have disregarded the established scientific empirical principles in their reports in determining a causal connection between the use of biocidal ingredients in wood preservatives and adverse health effects. The factual complaint is justified because the regional court relies on "findings of recent medical research" without presenting the criticism expressed against these findings in science to the necessary extent and without dealing with it objectively.

The Senate, however, is unable to follow the defense's view that the judge, taking into account the principle of doubt, is not allowed to establish causal relationships if their existence and course have not yet been scientifically clarified, but rather controversial.

It is not the task of the judge to use the investigation methods of the natural sciences to gain or refute new knowledge, in particular scientific empirical principles. Rather, the judge has to determine and assess certain facts in accordance with the rules of procedural law and with the evidence provided for this purpose, including, for example, witness evidence. The determination of the facts that are important for the criminal proceedings, in particular the proof of causal connections, does not require an absolute certainty that cannot be questioned by anyone; Rather, it is sufficient to have a sufficient level of security obtained with the means of criminal proceedings, based on life experience, which leaves no reasonable doubt (st. case, cf. only BGHR StPO § 261 formation of convictions 2).

This principle also applies to the recording and interpretation of processes that can be the subject of scientific research. There is no absolutely certain knowledge - also of causal connections - against which the existence of a contrary event can be ruled out with certainty (cf.RGSt 61, 202, 206; RGSt 66, 163 f; BGH GA 1954, 152; Herdegen StV 1992, 527 , 530). However, if a determination can only be made with the help of scientific methods, then the judge must not break away from scientific standards. The demands made on the formation of judicial convictions are then no less demanding than on the results of scientific investigations themselves (cf. BGHR StPO § 261 Expert 5).

For legal reasons, however, the judge is not prevented from relying on research results that are the subject of a scientific dispute after hearing experts. The obligation to provide comprehensive information can even require him to inform himself about methods and procedures that are not yet generally recognized. When assessing the evidence, however, he has to take into account the arguments for and against the not yet generally recognized methods and results (cf. BGH, decision of January 12, 1994 - 5 StR 620/93 = StV 94, 227). In addition, the judge has to assess the scientific findings and other circumstantial facts in an overall assessment. He can come to results that representatives of the relevant scientific disciplines could not prove with their methods alone. When considering natural scientific findings and other circumstantial facts, it must be taken into account that an expert can contribute to the establishment of the truth even if he is unable to draw reliable and unambiguous conclusions, but his conclusions make the facts to be proven more or less likely (BGHR StPO § 244 para. 3 sentence 2 unsuitability 2, 6). However, the judicial assessment must not contradict the laws of logic and the secured scientific experience (BGHR StGB before § 1 causality - omission 1).

For the present case this means: Even if there is no agreement among the natural scientists as to whether and in what way the poisons to which the injured parties have been exposed cause damage to health, the judge can, on the basis of an assessment of all relevant evidence and the scientific opinions, be free of legal errors come to the conclusion that exposure to wood preservatives has in certain cases led to health problems. A causal relationship between exposure to wood preservatives and a disease cannot only be demonstrated by either scientifically demonstrating the effects of the wood preservative ingredients on the human organism or by listing and excluding all other possible causes of a disease. Rather, other causes can be excluded - without their full discussion - if, after an overall assessment of the scientific findings and other circumstantial facts, the - at least - contributory cause of the wood preservative is established beyond doubt. With this decision, the judge would neither violate "recognized scientific empirical principles", nor would he instead of the specialist groups appointed to rule on the "existence of a timeless natural law"; which is in fact not due to him (see Kaufmann JZ 1971, 569, 574; Bruns, Festschrift für Maurach pp. 469, 478 f; Maiwald, Kausalität und Strafrecht 1980 b. 108, 109).

It is true that the determination made for a specific case on the basis of an overall assessment about the effect of a substance also more incidentally contains a statement about its general effectiveness. If the judge makes such a finding, then he does not decide the scientifically controversial question "about the existence of a natural law", but merely fulfills his task of deciding the specific legal case on the basis of the current state of knowledge, also considering all relevant evidence, if he - as in the overwhelming majority of the cases to be decided by him - cannot (yet) rely on scientifically proven empirical sentences when assessing evidence. However, if the judge relies on methods or findings that are not yet generally scientifically recognized, he must enable the appellate court to check whether the considerations for and against the methods or findings have been weighed up without any legal errors (see BGH aaO = StV 94, 227; BGHR StPO § 261 experience sentence 5).

In the grounds of the judgment, he must provide all the facts that the appellate court needs in order to check the conclusiveness of the controversial expert opinion and its compatibility with established scientific findings.

The judgment under appeal does not meet these requirements.

The criminal chamber based its findings on the health-damaging effects of the biocidal ingredients of wood preservatives, in particular the assumption that these have an immunosuppressive effect, also on the expert opinion of Prof. Dr. Hu .. The bases of this report are - as the contested judgment indicates - exposed to a variety of scientific criticism.

In this situation, the regional court should have reproduced the factual arguments of the critics and dealt with them. That did not happen here to the necessary extent. The criminal chamber only states that the "diverse scientific criticism" could not shake the content of the study (by Prof. Dr. Hu.).

The reasons for the judgment also show that the expert Prof. Dr. P. the report of the expert Prof. Dr. Hu. described as scientifically unfounded. The regional court presented the opinion of Prof. Dr. P. does not provide sufficient information, but only discusses individual questions selectively. It comes to the conclusion that the views of Prof. Dr. P. on the consequences of a T-cell defect would not correspond to the state of medical knowledge. The observations of Prof. Dr. Hu. however, documented the findings of more recent medical research.

The judgment under appeal does not reveal what the regional court is based on. It does not go without saying that Prof. Dr. Hu., Who, according to the findings of the judgment, is a nephrologist, has more recent knowledge in the field of immunology than the immunologist Prof. Dr. P ..

The inadequate presentation of the scientific dispute and the inadequate dispute between the regional court and the parties against Prof. Dr. Hu. concerns raised gives rise to concern that the criminal division has overestimated the probative value of this report.


The public prosecutor complains that the regional court wrongly denied an intentional commission and wrongly convicted the accused only of negligent bodily harm in the act of negligent release of poisons.

The appeal is unfounded.

On the one hand, the defendants are accused of producing and selling wood preservatives containing biocides for indoor use after the beginning of 1978. On the other hand, they are accused of not recalling dangerous products that have already been delivered and of failing to warn consumers who have already used these products.

The regional court justified the accusation of negligence with the fact that the accused should have noticed when studying the toxicological literature that there was practically no scientifically founded knowledge about chronic long-term exposure in the low dose range. Despite the current discussion about the use of biocidal active ingredients in indoor spaces since the late 1970s, neither industrial research nor private initiatives have devoted themselves to observing the possible consequences of inhalation of these toxins in living spaces. This gap should have been filled by the defendants, who had the research capacities of the co-partner at the time, the company B., at their disposal to research the damage. The district court does not consider an intentional inspection to be proven because the defendants considered the wood preservatives to be harmless and this view was confirmed by scientists.

This judicial evaluation is not objectionable for legal reasons. According to the findings of the regional court, the defendants were convinced "right up to the day of the main hearing" that the houses treated with wood preservatives only had low levels of toxicity and that no health damage could occur. According to this, the accused can only be accused of unconscious negligence, which differs from conditional intent both in the "element of knowledge" and in the "element of will". The regional court did not make any determinations that could justify the assumption of a conditional resolution. Even if the defendants should have seriously considered that the use of the wood preservatives they sell leads to damage to health, the overall circumstances of the defendants suggest that they ultimately trusted the harmlessness of the products. They themselves had a great interest in ensuring that the products of the company they represented did not fall into disrepute and that this company would not be exposed to claims for damages (see also BGHR StGB § 15 intent, conditional 1, 6, 9; StGB § 306 Evidence Assessment 6 ).

The complaints filed against the decision on costs and probation are irrelevant.

External sources: BGHSt 41, 206; NJW 1995, 2930; NStZ 1995, 590; StV 1997, 124

Editor: Rocco Beck