Ask HN: Web Site Accessibility Guidelines for a bill draft?

The political party I'm affiliated to is drafting a bill on Web Site Accessibility, aiming to make the public websites adhere to accessibility guidelines, and I've been asked to give my opinion as an advisor. So far we've agreed to follow the W3C WAI guidelines - is there a better set of guidelines we should be adhering to, or something else we should be taking into account? Anyone here is involved in website accessibility, do you take it into account when building your websites? Thanks!