In 2013, the UC Electronic Accessibility Leadership Team (EALT) proposed a new systemwide accessibility policy, which included the requirement that all websites should meet the WCAG 2.0 Level AA Success requirements.
Reference
For a guide on how to meet AA Level requirements, use the W3's customizable quick reference.
Agencies Who Enforce Access
The United States Access Board
The United States Access Board covers Accessible Design and sets standards for architecture and design. They set rules and standards for such things as size, distribution and arrangement of disabled parking spaces, wheelchair access for theatres, design guidelines for talking or chirping crosswalk indicators, etc.
U.S. Department of Education
The U.S. Department of Education, Office for Civil Rights enforces Section 504 as it applies recipients of Federal Funding for education.
U.S. Department of Justice
Section 508 requires all federal government bodies and their contractors to make Information Technology accessible for the disabled.
The Federal Communications Commission (FCC)
The FCC coordinates Section 255 of The Telecommunications Act. They require the telecommunications industry to make equipment readily accessible or, alternatively, make equipment compatible with assistive technology devices.