38 CFR 3.200: Testimony certified or under oath.

(a) All oral testimony presented by claimants and witnesses on their behalf before any rating or authorization body will be under oath or affirmation. (See § 3.103(c).)

(b) All written testimony submitted by the claimant or in his or her behalf for the purpose of establishing a claim for service connection will be certified or under oath or affirmation. This includes records, examination reports, and transcripts material to the issue received by the Department of Veterans Affairs at the instance of the claimant or in his or her behalf or requested by the Department of Veterans Affairs from State, county, municipal, recognized private institutions, and contract hospitals.