The Disability Discrimination Act 1995 (DDA) is "an Act to make it unlawful to discriminate against disabled persons in connection with employment, the provision of goods, facilities and services or the disposal or management of premises; to make provision about the employment of disabled persons; and to establish a National Disability Council."
A brief guide to the DDA provides more information on the UK DDA.
While the Act itself does not directly address Internet sites, supporting documents clearly indicate that Internet sites can be covered under DDA.
The revised Code of Practice  provides the following clarifications and examples:
For people with [hearing disabilities or visual impairments], the range of auxiliary aids or services which it might be reasonable to provide to ensure that services are accessible might include one or more of the following: ... accessible websites
An airline company provides a flight reservation and booking service to the public on its website. This is a provision of a service and is subject to the Act.
The guidelines for UK Government websites  state:
Part III of the DDA makes it unlawful for a service provider to treat disabled people less favourably for a reason related to their disability. Service providers must also consider making reasonable adjustments to the way that they deliver their services where disabled people find these impossible or unreasonably difficult to access.
There are provisions in the Disability Discrimination Act (section 19 (3)) that state that "access to and use of means of communication", and "access to and use of information services", are both examples of services which would be covered by Part III.
However, it would be for a court to decide whether it would have been reasonable for a particular service provider to have made a particular adjustment to enable access for a disabled person, taking into consideration all the circumstances of the case.
Government policy is to encourage departments and agencies to make their services as accessible to disabled people as is reasonably possible. These guidelines have been developed with this aim in mind.
An article published in the Journal of Information, Law and Technology states:
Level A [of WCAG] would be a realistic and clear standard for the Courts to set as an initial benchmark for DDA compliance.
The obligation to follow 'recognised standards and practices' would surely include a requirement to design the Web site with WAI Guidelines compliance
An article published by The International Centre for Commercial Law states:
The Web Accessibility Initiative has published Web Content Accessibility Guidelines (WCAG). Although the WCAG does not have any legal effect in the UK, a minimum standard of web accessibility could be interpreted to mean compliance with all Priority 1 checkpoints of the WCAG.A Government Communications White Paper  states:
We support the work undertaken by the body charged with setting standards for the Web, the W3 Consortium, on making the Web accessible to people with disabilities.Furthermore, legal activity in the U.S. and Australia supports using WCAG as a measure of web accessibility.
We are preparing constructive aids to assist our webmasters and web managers to understand accessibility problems and to enhance our compliance with the WAI. Our core guidance will recommend that our online services are at minimum WAI - A compliant.