Art. 55 para. 1 of the Code of Obligations (CO) provides that an employer is liable for damage caused by their employees or other auxiliaries in the performance of their work, unless they prove having taken all the care required by the circumstances to prevent damage of that kind. This provision establishes a liability based on a presumption of fault — known as the presumption of culpa in eligendo, instruendo et custodiendo — which lies with the employer once the conditions for its application are met. The burden of proof is thus reversed: it is for the employer to demonstrate their diligence, not for the victim to prove fault.
The framework of art. 55 CO
Art. 55 CO is a rule of non-contractual (tortious) liability that protects third parties — that is, persons who are not party to a contract with the employer — against damage caused by the unlawful acts of auxiliaries in the exercise of their activity. It falls within the general system of civil liability defined in art. 41 et seq. CO.
The employer's liability under art. 55 CO has two essential characteristics:
- Presumption of fault: the law presumes that the damage results from a lack of diligence by the employer in the selection, instruction or supervision of the auxiliary. This presumption may be rebutted by exculpatory proof.
- Liability for others: the employer is answerable for conduct they did not personally engage in, but which was committed by a person they use in their activity.
Art. 55 CO does not provide for pure causal liability (unlike, for example, the liability of the keeper of a vehicle under the Road Traffic Act): the employer has a statutory escape route if they prove their diligence.
The concept of auxiliary
The concept of auxiliary within the meaning of art. 55 CO is broader than that of employee under employment law. An auxiliary is any person used by the employer to carry out their activity or fulfil their obligations, whether the legal link is an employment contract, a mandate contract, an apprenticeship, an internship or any other relationship. The existence of an employment contract is not required.
Legal doctrine and practice generally apply the following criteria to characterise a person as an auxiliary:
- The auxiliary acts in the interest of the employer or on their behalf
- The employer holds a power of direction or instruction over the manner of performing the task
- The damaging act occurs in the performance of the work entrusted, and not in a purely private context
It is important to distinguish the auxiliary within the meaning of art. 55 CO (tortious liability) from the auxiliary within the meaning of art. 101 CO (contractual liability). In the first case, the relationship is assessed in relation to third parties; in the second, in relation to the employer's contracting party.
Conditions for the application of art. 55 CO
For the employer's liability to be engaged under art. 55 CO, four cumulative conditions must be met:
- An unlawful act by the auxiliary: the auxiliary must have committed an act which, in itself, would constitute tortious civil liability within the meaning of art. 41 et seq. CO (violation of a rule of law, infringement of an absolute right, etc.).
- Damage: the victim must have suffered a financial loss or, in cases provided by law, non-material damage (art. 47 and 49 CO).
- A natural and adequate causal link between the auxiliary's act and the damage.
- The act must have been committed in the performance of the entrusted work: there must be a functional link between the task assigned and the damaging act. An act committed entirely outside any relation to the entrusted work does not engage the employer's liability.
The employer's personal fault is not a condition of application: the law presumes such fault. This is the central mechanism of art. 55 CO.
Exculpatory proof
The employer may be exonerated from liability by proving that they took all the care required by the circumstances to prevent damage of the type that occurred. This exculpatory proof, expressly provided for in art. 55 para. 1 in fine CO, relates to three levels of diligence:
- Cura in eligendo (diligence in selection): the employer must have selected the auxiliary carefully, verifying their qualifications, aptitude and seriousness for the task to be performed.
- Cura in instruendo (diligence in instruction): the employer must have given the auxiliary clear, adequate and sufficient instructions to enable them to perform the task without causing damage to third parties.
- Cura in custodiendo (diligence in supervision): the employer must have exercised appropriate supervision over the auxiliary in the performance of the task.
Exculpatory proof is assessed in light of the concrete circumstances: the more dangerous the activity, the higher the standards of diligence required. It is not sufficient to have put general safety measures in place; those measures must also be adapted to the specific risks of the activity in question. In practice, courts rarely accept this exculpatory proof.
Interplay with contractual liability (art. 101 CO)
Art. 101 CO governs the debtor's liability when they use auxiliaries to perform their contractual obligations. The regime is fundamentally different from that of art. 55 CO:
| Criterion | Art. 55 CO (tortious liability) | Art. 101 CO (contractual liability) |
|---|---|---|
| Scope of application | Non-contractual relationships (with third parties) | Contractual relationships (with the contracting party) |
| Nature of liability | Presumption of fault (rebuttable) | Objective liability (non-rebuttable) |
| Exculpatory proof | Yes: proof of diligence (selection, instruction, supervision) | No: no exculpatory proof by diligence |
| Severity | Less strict (exoneration possible) | Stricter (full liability) |
| Contractual exclusion | Possible within the limits of art. 100 CO | Limited (art. 100 para. 1 CO: excluded for gross negligence) |
| Legal basis | Art. 41 et seq. CO (general civil liability) | Non-performance or defective performance of contract |
Where the same damaging act causes both contractual and tortious damage (for example, a service provider who simultaneously causes harm to their client and to a third party), the two regimes may apply concurrently, but their conditions of application and effects must be analysed separately.
Civil liability and criminal liability — distinction
The employer's liability for their auxiliaries under art. 55 CO is a civil liability, distinct from criminal liability. This distinction is fundamental:
- Civil liability (art. 55 CO): aims to compensate the victim for the damage suffered. The employer is required to pay damages and, where applicable, compensation for non-material harm. The fault of the auxiliary is presumed; so is that of the employer. The action belongs to the victim (or their heirs).
- Criminal liability: aims to sanction reprehensible conduct. Under Swiss law, criminal liability is personal (art. 7 CC): the employer cannot be held criminally liable for the acts of their auxiliaries unless they personally committed an offence (for example, a punishable failure of supervision, or a corporate criminal law offence within the meaning of art. 102 CC for certain specific offences).
Art. 102 CC provides for criminal liability of a legal entity for certain offences where, due to a lack of internal organisation, the offence cannot be attributed to any specific natural person. This criminal liability of the enterprise is separate and independent from civil liability under art. 55 CO.
On a procedural level, a criminal conviction of the auxiliary does not automatically prejudge the civil liability of the employer, and vice versa. The two proceedings follow different rules of evidence and different standards.
Recourse against the auxiliary (art. 55 para. 2 CO)
Art. 55 para. 2 CO expressly reserves the employer's right of recourse against the auxiliary responsible for the damage. The employer who has compensated the victim is thus subrogated to the victim's rights and may seek recourse against the negligent auxiliary.
This recourse is nevertheless governed by the rules of employment law, in particular art. 321e CO, which governs the employee's liability towards the employer. Under that provision, the employee's liability is modulated according to:
- The degree of fault: in the event of slight fault, the recourse may be reduced or excluded, particularly where professional risk is inherent in the activity performed; in the event of gross or intentional fault, the recourse will in principle be admitted in full.
- The professional risk: normal risks inherent in the performance of the work should not be borne entirely by the auxiliary if they committed only slight fault.
- The hierarchical position and experience of the auxiliary: an experienced person holding a position of responsibility will be held to a higher standard of diligence.
The employer's right of recourse against the auxiliary is subject to the ordinary limitation periods (see below). It should be noted that the employer cannot, in principle, agree in advance with the auxiliary on a total exclusion of the latter's liability if that would circumvent the statutory requirements.
Special case of temporary work and staff leasing
Temporary work (or staff leasing within the meaning of the Federal Act on Employment Agencies, LEA) raises specific questions regarding the application of art. 55 CO. In that context, a distinction must be drawn between two actors: the formal employer (the temporary employment agency, which is the employer under the employment contract) and the de facto employer (the client company, which actually directs the temporary worker).
Case law and legal doctrine generally accept that:
- The client company (de facto employer) may be held liable under art. 55 CO for damage caused by the temporary worker it directs, as it exercises effective supervisory and instructional power during the assignment.
- The temporary employment agency (formal employer) remains, in principle, liable for obligations arising from the employment contract and may also be sued if a deficiency in the selection or presentation of the worker is established.
In practice, secondment contracts between the temporary employment agency and the client company generally include clauses on the allocation of liabilities and indemnification. Such clauses are valid within the limits of art. 100 CO.
Prescription (art. 60 CO)
Actions based on art. 55 CO are subject to the limitation periods of art. 60 CO, as revised upon the entry into force of the new prescription law on 1 January 2020:
- 3 years from the day the injured party became aware of the damage and of the person liable for compensation (relative period).
- 10 years from the day the damaging event occurred or ceased (ordinary absolute period).
- 20 years from the day the damaging event occurred or ceased, where the damaging act is a criminal offence punishable by a longer custodial sentence (art. 60 para. 1bis CO, introduced in 2020).
The limitation period may be interrupted by the acts provided for in art. 135 et seq. CO, in particular by an acknowledgement of debt, debt enforcement proceedings or a legal action. Particular attention must be paid to compliance with these periods, as a time-barred claim will be dismissed regardless of the merits of the substantive claims.
In the event of a concurrence between liability under art. 55 CO and contractual liability, the applicable limitation periods are those corresponding to the nature of each claim.
Frequently asked questions on employer liability for auxiliaries
Who is considered an auxiliary within the meaning of art. 55 CO?
An auxiliary is any person used by the employer to carry out their work or fulfil their obligations, whether under an employment contract, a mandate, or any other legal relationship. The term is interpreted broadly by legal doctrine: it may include an employee, an apprentice, a trainee, or even a subcontractor under certain conditions. The essential point is that the auxiliary acts in the employer's interest or on their instructions at the time the damage occurs. The status of auxiliary does not require the existence of a subordination relationship in the strict sense of employment law.
How can an employer be exonerated from liability under art. 55 CO?
Art. 55 para. 1 CO offers the employer an exculpatory proof: liability is avoided if the employer demonstrates having taken all the care required by the circumstances to prevent damage of that kind (cura in eligendo, instruendo et custodiendo). In practice, the employer must prove (1) that they carefully selected the auxiliary for the task to be performed, (2) that they gave adequate instructions, and (3) that they exercised appropriate supervision. This proof is assessed strictly: the more dangerous the activity or the more sensitive the task, the higher the standard of diligence required. In practice, this exoneration is rarely accepted.
What is the difference between art. 55 CO and art. 101 CO?
Art. 55 CO governs the employer's tortious liability for unlawful acts committed by their auxiliaries against third parties, with a rebuttable presumption of fault. Art. 101 CO governs the debtor's contractual liability for their auxiliaries vis-à-vis the contracting party: in that case, liability is objective and cannot in principle be excluded by proof of diligence. In other words, art. 101 CO is stricter than art. 55 CO because it does not provide for a comparable exculpatory proof. The scope of application differs: art. 55 CO applies outside contract (tortious liability), while art. 101 CO applies within an existing contractual relationship.
Is a subcontractor an auxiliary of the main contractor within the meaning of art. 55 CO?
In principle, no. Liability under art. 55 CO requires the employer to exercise a power of direction over the auxiliary and for the auxiliary to act within the employer's sphere of activity. A subcontractor is generally a legally independent entity that performs its own work under its own responsibility, and is not in a relationship of subordination with the main contractor. However, if the main contractor exercises effective control over the manner of performance of the subcontractor, or if the subcontractor is integrated into the contractor's organisation, the characterisation as an auxiliary may be required. Each situation must be assessed on a case-by-case basis. In the contractual sphere, the question is resolved differently under art. 101 CO.
Can the employer seek recourse against the auxiliary after compensating the victim?
Yes. Art. 55 para. 2 CO expressly reserves the employer's right of recourse against the negligent auxiliary. The employer who has compensated the injured third party may bring an action for indemnification against the auxiliary to the extent that the auxiliary is liable for the damage. However, the amount of the recourse is limited by art. 321e CO (employee's liability towards the employer), which takes into account the degree of fault and professional risk. In the event of slight fault, the recourse may be reduced or even excluded. In the event of serious or intentional fault on the part of the auxiliary, the recourse will in principle be granted in full.