Telephone monitoring in the workplace



   Surveillance of employees: telephone monitoring in the workplace 



Telephones are one of the most common means of communication in the workplace. They are used for both professional and personal reasons. Telephone monitoring by the employer is limited by law and failure to comply with the rules can lead to sanctions.

Legality of telephone monitoring in the workplace and claims


Types of telephone monitoring

Private conversations

Employers are not allowed to listen to or record private conversations, because such data is not necessary for ensuring compliance with an employment contract (Art. 328b CO), and because it constitutes a violation of an employee's personality rights (Art. 328 CO; art. 26 EmpO 3); a failure to comply with the law  may lead to prosecution (Art. 179bis SCC).

If telephone monitoring is necessary to collect evidence in the context of a criminal investigation, it must be carried out on the orders of the competent authorities. The provisions relating to the defence of  necessity (Art. 17 SCC) remain reserved. In this case, the employer must let the competent authorities take charge of any further monitoring.

Business conversations

The employer is permitted to listen to or record conversations for the following purposes: performance and quality control; training; security (see also explanations: 'Monitoring of employees: Legal framework and conditions for telephone monitoring in the workplace').

The Criminal Code requires the consent of all participants as a precondition for listening to or recording conversations (Art. 179bis SCC). The persons whose conversations are being recorded or listened to must be informed clearly and in advance. In addition, they must give their consent.

Informing the persons whose data is processed (the data subjects) in advance also makes it less likely that they will have private conversations that might be listened into or recorded It is not necessary to repeat this information in every telephone conversation if listening in or recording is systematic and the callers have already been clearly informed. This solution is feasible in some banking sectors where transactions have to be handled by telephone. The existence of a listening or recording system should be mentioned in the employment contract for employees and in the general conditions of business for customers.
A further solution is to play a pre-recorded message informing callers to a company that telephone conversations may be listened into or recorded. This solution is particularly suitable for persons who are not contractually bound to the company concerned.

Call centres may occasionally listen into or record conversations with callers. As a rule, whenever it happens, employees are informed by means of a visible or audible signal that conversations are being listened into or recorded. When assessing the effectiveness of training, it is acceptable under the provisions on the protection for employees to be informed that conversations will be listened into or recorded for a certain period of time. In this case, employees must be informed in good time and in a clear manner, e.g. on the employer's intranet site, of the period during which they are likely to be subject to such monitoring. The principle of proportionality and the protection of personality rights and health in the workplace require that these periods be of proportionate length and frequency. Of course, the duty to inform other callers still applies (e.g. by playing a pre-recorded message at the start of the conversation).

The recording of calls to emergency, rescue or security services is not a criminal offence, nor is the recording of telephone conversations in the course of business that have orders, assignments, reservations and similar transactions as their subject matter (Art. 179quinquies SCC). 

Monitoring of technical data

Employers are permitted to systematically monitor technical data relating to calls to check whether the internal regulations are being observed, but also for billing the employee or customer. This monitoring may cover the following data: the caller’s number; outgoing private call numbers, but only the area code; numbers of outgoing business calls; date and time of the calls; duration; cost of the calls; information on the type of call (landline or mobile network); details of the regional fees: national or international call (+ countries). 
Technical data on telephone calls should not be kept for more than six months

Monitoring of potentially criminal activities

If an employer has good reason to suspect that an offence has been committed or is about to be committed by telephone, he or she can log the technical data relating to the use of the telephone. The employer's suspicions must relate to an employee behaving in a manner that not only is a breach of the employment contract or telephone use regulations, but is also a criminal offence. Examples of offences that could be committed by telephone include criminal defamation (Art. 173 SCC) and sexual harassment in the workplace (Art. 198 SCC).
Ordering the monitoring of the content of conversations to gather evidence or confirm a suspicion is a matter for the prosecution authorities. Employers should not take the initiative to eavesdrop on or record telephone conversations. The prosecution authorities will order surveillance measures if an overriding private or public interest in doing so is established. Employers must treat the information obtained through monitoring as confidential with respect to third parties, in particular their other employees. The sanctions provided for in employment law for a violation of the rules on the use of the telephone are reserved.

Employees' claims in the case of unlawful surveillance

Employers who do not comply with the rules and conditions on telephone monitoring can be sued for an unlawful infringement of personality rights (Art. 32 and 41 FADP).

Data subjects can assert their claims (to establish unlawful conduct, obtain damages, etc.) against the employer. If an employer does not respond to the employee's claims, the matter may be taken to an employment tribunal. 
In the case of improper surveillance, employers may also face criminal proceedings, for example if they are suspected of listening into or recording a conversation without consent (Art. 179bis SCC).

Legal framework and rules on telephone monitoring in the workplace

Telephones are one of the most common means of communication in the workplace. They are used for both professional and personal reasons. Employers are required to comply with a number of rules regarding telephone monitoring.

Legal framework

The use of telephones in the workplace raises many questions, in particular whether or not telephones can be monitored by the employer for performance control, quality control or training purposes. In addition to informing the persons whose telephones are monitored, employers who take such a measure must, among other things, comply with the general principles of data protection and the provisions of Ordinance 3 to the Employment Act. Moreover, the Code of Obligations expressly provides that an employer is obliged to protect and respect the personality rights of the employees, in particular their privacy (Art. 328 CO).
For their part, employees must perform the work assigned to them with due care and loyally safeguard their employer's legitimate interests (Art. 321a CO). The use of surveillance systems to monitor compliance with telephone regulations may constitute a violation of the worker's privacy if certain conditions are not met (Art. 26 of Ordinance 3 to the Labour Act EmpO 3).
Employers must protect telephone communication data by taking technical and organisational measures against unauthorised use of such data. In particular, they should ensure the confidentiality, availability and accuracy of the data (Art. 3 of the Ordinance to the Federal Act on Data Protection OFADP). Employees may at any time ask their employer whether data concerning them are being processed and, if so, which data and for what purpose (Art. 25 FADP).

As to whether an employer can check whether employees are using their work telephones for private purposes, it is worth pointing out that a telephone conversation can only be recorded in the context of a performance check or for security reasons; However, the person concerned must be informed in good time and in a clear manner before the recording (e.g. by a visual or acoustic signal). The employer should not monitor telephone calls as a way of enforcing a ban on private use of work telephones (e.g. by having external communications routed through a central switchboard or making external calls possible only with certain phones). 

Data relating to private telephone calls are private and should not, in principle, be recorded. If there are specific indications that an employee is making excessive use of his or her work telephone for personal calls (e.g. there is a legitimate suspicion if costs charged to an employee's work telephone are unreasonably high or if it is used to make repeated personal calls), the data subject must be informed that use of his or her work telephone for personal calls has been detected and that all call data may be recorded and evaluated. Employees in this situation must be given the opportunity to explain themselves. Employers are obliged to treat the private data they have examined as confidential. It should be noted that the recording of telephone data should not be used to monitor the behaviour of employees.

Rules that apply to telephone monitoring

There are no regulations on the use of work telephones, making it difficult to know how they should be used or not. If there is no express restriction or prohibition on private calls in the workplace, employees may assume that private telephone use is permitted, within reason, and that calls are not being monitored. 

Whether the employee has the right to use the telephone for private purposes depends primarily on what the employer decides (right to issue directives and instructions, Art. 321d CO). It is worth pointing out that even if making private calls is prohibited in the workplace, receiving private calls is not.

Publishing regulations on telephone use is the right step to take, even if it is not compulsory. Written regulations ensure transparency and legal certainty in the relationship between employer and employee. Regulations communicated by word of mouth are just as binding, but can be difficult to prove in the event of a dispute.

Regulations can determine whether private calls are allowed, restricted or prohibited. There are several ways to limit employees from making private calls, including blocking the facility to dial international numbers, blocking certain numbers, or scheduling times when private calls are allowed. Many companies cover the cost of private calls for their employees up to a pre-determined amount.

Although regulations are not mandatory, employers have a duty to inform their employees of any monitoring of their telephone calls, as this may constitute a violation of the employees' privacy (principle of good faith, Art. 6 para. FADP). This information must include the monitoring system used and the modus operandi. Employees should be informed in advance of any monitoring and of any potential sanctions.

Employees should also be informed, where appropriate, that a system for recording telephone conversations has been set up to monitor performance or keep a record of what is said for evidential purposes and the conditions associated with such monitoring should be explained. It is also advisable to inform the those concerned who is responsible for logging the calls or listening in on conversations, what specific sanctions can be taken in terms of employment law and how criminal proceedings can be brought in the event of suspicion. Finally, the difference between private and business calls should be explained. The information provided to employees should also include access rights, content and retention period of the logged data.

Employers are therefore advised to draw up regulations for telephone monitoring in writing. This will ensure transparency and legal certainty. These regulations should be attached to the regulations on telephone use in one document. 

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The main provisions

Here you can find out more about changes to the Data Protection Act, which came into force on 1 September 2023.

Last modification 19.06.2023

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