28 CFR Part 36 Nondiscrimination on the Basis of Disability by Public Accommodations and in Commercial Facilities (2010 ADA Title III Regulations with amendments issued through Dec. 2016)

(8) Prevention of fraud in purchase of tickets for accessible seating. A public accommodation may not require proof of disability, including, for example, a doctor's note, before selling tickets for accessible seating.

(i) Single-event tickets. For the sale of single-event tickets, it is permissible to inquire whether the individual purchasing the tickets for accessible seating has a mobility disability or a disability that requires the use of the accessible features that are provided in accessible seating, or is purchasing the tickets for an individual who has a mobility disability or a disability that requires the use of the accessible features that are provided in the accessible seating.

(ii) Series-of-events tickets. For series-of-events tickets, it is permissible to ask the individual purchasing the tickets for accessible seating to attest in writing that the accessible seating is for a person who has a mobility disability or a disability that requires the use of the accessible features that are provided in the accessible seating.

(iii) Investigation of fraud. A public accommodation may investigate the potential misuse of accessible seating where there is good cause to believe that such seating has been purchased fraudulently.