Hardly any law firm or practice works alone. Assistants, secretaries, trainees and external providers gain insight into information subject to professional secrecy. The Criminal Code takes account of this by binding auxiliaries too.
Internal auxiliaries
Staff who help the professional in their work are classic auxiliaries: secretaries, legal staff, assistants, trainees, interns. They are themselves bound by professional secrecy. For lawyers, Art. 13 of the Lawyers Act expressly requires them to ensure that their auxiliaries preserve professional secrecy — through selection, instruction and supervision.
External providers
The question is harder for external providers such as IT support, cloud vendors, translation agencies or AI services. Whether they count as auxiliaries depends, on a widely held view, on how closely they are integrated into the professional work and whether they are subject to the professional’s instructions. The question is disputed in legal writing. In practice, a cautious approach that holds regardless of classification has therefore proven itself.
What applies in practice
External providers are bound to confidentiality by contract and informed about professional secrecy. They receive only the access their task requires. Data is encrypted where possible so the provider cannot see it in clear text. Use of the information for their own purposes, such as training AI models, is excluded. And the professional selects the provider carefully and checks compliance. When in doubt, consulting the competent professional body is advisable.
What it means for AI tools
The same principles apply to AI tools as to other external services, with two particularities: many consumer offerings allow the provider to use inputs, and processing location and retention are often not contractually defined. For client information, therefore, only business access with a contract and training excluded qualifies. The review is described in our AI vendor vetting checklist.