Following established guidelines such as WCAG 2.0 is important.
Normally people aim to meet level AA this means that many of the major issues of interoperability with assistive technology are removed. I would urge policy makers to examine the practicality of also looking to implement some of the AAA criteria as these are particularly beneficial for people with cognitive accessibility needs.
Please also look at the work of the W3C cognitive accessibility taskforce to get more information on how we can better make the internet a place that welcomes people with the widest possible range of needs not just the obvious disabilities that have established ways and means of delivering access.
PS the irony of using a Captcha on this form enquiring about accessibility is exquisite