28 CFR Part 35 Title II Notice of Proposed Rulemaking (NPRM) (published 2008)

(g) Access to areas open to the public, program participants, and invitees.  Individuals with disabilities who are accompanied by service animals may access all areas of a public entity's facility where members of the public, program participants and invitees are allowed to go, unless the public entity can demonstrate that individuals accompanied by service animals would fundamentally alter the public entity's service, program, or activity.