I wonder what types of websites, if any, must respect the Web Content Accessibility Guidelines in the United States?
I am especially interested in the application of a minimum contrast.
Law Stack Exchange is a question and answer site for legal professionals, students, and others with experience or interest in law. It only takes a minute to sign up.Sign up to join this community
There are at least three kinds of "must" implied by the question. The broadest is the non-legal "in order to avoid all negative consequences", in which case probably any and all. From the legal POV, you can distinguish two varieties of compulsion, one being ordinary tort or contractual liability. Theoretically, I could try to sue anybody that uses color distinctions to convey information on a web page. As an out-of-the-blue web surfer (no pun intended) I would probably have no luck. However, I might have a contractual relationship with a website, where I pay big money and they provide me information, only they do it via virtually imperceptable color differences like 123456 vs 123459. It is possible (but certainly not a foregone conclusion) that they would be in breach of the agreement. One would have to look at the contract. That then leaves the possibility that there is a federal or state regulation that obligates some/all web pages to comply with certain standards (which could lead to a discrimination suit). The short answer is, there aren't any across-the-board requirements. There are very many specific requirements.
To the best of my knowledge, the two relevant pieces of law are the Americans with Disabilities Act and the Rehabilitation Act. Whether or not you have to do something to comply with these acts depends on what you are doing. One reason would be in connection with employment: as an employer, I have some legal obligation to comply. Regarding 42 USC 12111, an employer is
a person engaged in an industry affecting commerce who has 15 or more employees for each working day in each of 20 or more calendar weeks in the current or preceding calendar year, and any agent of such person, except that, for two years following the effective date of this subchapter, an employer means a person engaged in an industry affecting commerce who has 25 or more employees for each working day in each of 20 or more calendar weeks in the current or preceding year, and any agent of such person
and then it mentions exclusions, such as an Indian tribe, or the US, or a corporation owned entirely by the US government, etc. As an employer, I would have to make reasonable accommodations for a qualified individual (these are terms defined in the statute). The latter may include "making existing facilities used by employees readily accessible to and usable by individuals with disabilities". If the web page (which the employee has to use on the job) employs the color scheme "light greenish yellow vs. light yellowish green" for conveying important information, and if that could be trivially re-coded to black and white by changing two constants, then that would be a reasonable accommodation (probably), where if it required massive and expensive reprogramming, that would not be reasonable. Even then, it would depend on the disability in question. There is a federal agency, the Equal Employment Opportunity Commission, which has jurisdiction over that and can decide what is a disability for their purposes. As far as I know, color blindness is not a protected disability, and the EEOC Q&A on vision impairment and ADA does not suggest that this is a protected disability. That page has extensive examples that you can work through to get a feel for who might be covered, and what accommodations are reasonable.
Pursuant to section 508 of the (amended) Rehabilitation Act, the Federal government has to provide access to information for disabled persons that is comparable to that available to others. An obvious example of that would be web pages that could be listened to rather than only being read. This doesn't per se apply to private web pages, as long as you are not receiving federal funds. Also, this is not an absolute requirement, so if it would impose an undue burden on the agency to comply, then they can be in less than full compliance. Even so, assuming that color-blindness is not yet a legal disability, the widespread color abuses on web pages are not legally covered.