Because there are no governing bodies (i.e., legal authorities) that certify websites as “ADA compliant”, the two best paths to website accessibility certification are a conformance statement and user testing report.
We will see more of a market demand for certification in 2023 as demand for accessible websites, products, and services continues to surge.
A conformance statement is a construct of the World Wide Web Consortium (W3C) under their Web Accessibility Initiative or WAI and must be be issued using their 5 requirements for a statement of conformance.
The most important requirement is that all of the URLs / pages listed as conformant must be fully conformant with a version of the Web Content Accessibility Guidelines (e.g., WCAG 2.1 AA conformant).
A conformance statement can only be issued after an audit and remediation takes place.
User testing performed by a panel of accessibility professionals with diverse disabilities is a more informal but highly practical way of certifying your website as accessible.
If you combine both a user testing report along with a statement of conformance, this is the ultimate answer to certifying your website is accessible and these reports could definitely help get a case dismissed.
And the work done to receive them would prevent litigation.
Note that a Voluntary Product Accessibility Template “VPAT” (or, more correctly, Accessibility Conformance Report “ACR”) is not traditionally for websites. However, if a website is considered part of the procurement process of an ICT product or service, a VPAT can be issued for a website.
In this case, a VPAT doesn’t necessarily “certify” a website as accessible. Rather, a VPAT would provide an accounting of the website’s accessibility. That said, if the website was mostly accessible / conformant, it would provide another means of informal certification.
One important aspect to these reports is they must be issued by a digital accessibility company with credibility and standing. If a company such as an overlay vendor (seller of accessibility widget) issues certification, the report will be questioned.
Relatedly, a report should never be able to be purchased itself. There may be a fee for certification on top of audit / remediation work, but you shouldn’t be able to purchase a certificate of accessibility.