(a) Burden of Proof. Except as otherwise specifically provided by law, the burden of proof is on the appellant as to all issues of fact, except that, in respect of any new matter first raised by the respondent during an appeal before OTA, the burden with respect to the new matter shall be on the respondent.

(b) Standard of proof. Except as otherwise provided by law, the burden of proof requires proof by a preponderance of the evidence.

(c) Fraud or evasion. In any proceeding involving the issue of fraud or intent to evade tax, the burden of proof as to that issue is upon the Agency by clear and convincing evidence.