Legal Context of Usability

Usability is not just a quality feature - it is also increasingly relevant from a legal perspective. Especially when accessibility, product liability or conformity with standards are required.

Definition according to ISO 9241-11

Usability refers to the extent to which a product can be used effectively, efficiently and satisfactorily by specific users in a specific context of use.

Why usability counts in legal terms

Usability is not just a design issue. It has a direct influence:

the legal security of digital products,
the fulfillment of legal requirements,
and the liability risk in the event of damage.

An error-prone form that misleads users can violate information obligations, for example. Or an inaccessible app can violate accessibility standards - with legal consequences for both public and private providers.

Relevant regulations and laws

👩‍⚖️ Accessible IT

Digital accessibility is a legal requirement for many services. This forms the basis:

BITV 2.0 (Barrier-free Information Technology Ordinance) - binding for German authorities
EN 301 549 - European standard for accessible software and hardware
European Accessibility Act - mandatory for commercial providers from 2025 (e.g. e-commerce, banking portals)

An accessible system must, for example, be able to be operated using a keyboard, be clearly understandable in terms of language and be compatible with screen readers.

📚 Standards with legal reference

ISO 9241-210: Requires a user-centered development process
ISO 9241-171: Regulates accessible software ergonomics
Product-specific standards (e.g. medical technology, industrial equipment) are increasingly integrating UX requirements

A company that ignores standard specifications risks liability in the event of damage - for example, if an operating error was caused by a lack of suitability for use.

Practical example: Accessible websites

A state portal uses icons without alternative texts and unstructured PDFs. A blind user cannot grasp essential information. This constitutes a violation of BITV 2.0. Following a complaint by the conciliation body, there is a threat of an adjustment order - possibly with sanctions.

Accessibility is therefore not a “nice-to-have”, but a legal obligation, compliance with which must be proven - e.g. through evaluations, test reports and comprehensible UX documentation.

Conclusion

Usability today is at the interface between design, technology and law. Those who implement it in a standard-compliant and user-centered manner benefit in several ways: through a better user experience, lower legal risks and clear evidence in audits or tenders.

Take Home Message

Usability not only protects users - but also providers.

Frequently asked questions (FAQ)

Why does good usability reduce liability risks?

Foreseeable usage errors can be avoided. Proven user-centered processes and tests reduce risks and demonstrate diligence.

How do I prove accessibility?

Through WCAG/BITV audits, usability tests, a documented UCD process and verifiable reports.

What role does the European Accessibility Act play?

From 2025, the EAA will require many digital products and services in the EU to be accessible. Violations can lead to sanctions and market bans.

Which standards are particularly important for legally compliant usability?

ISO 9241-11, ISO 9241-110 and ISO 9241-210 are key. Industry-specific standards also apply.

How can I prove compliance with standards?

Through test reports, documented usability tests, checklists and comprehensible UX documentation.

What happens if accessibility laws are breached?

There is a risk of adaptation orders, fines or claims for damages. Public bodies also risk exclusion from tenders.

What advantages does ISO-compliant usability bring beyond legal certainty?

It improves the user experience, reduces support costs and strengthens trust in digital products.

Last modified: 2 November 2025