Final answer:
The correct statement regarding the unauthorized practice of law is that a CPA cannot express a legal opinion on a non-tax matter unless they are also a licensed attorney. Taxpayers may draft their contracts and represent themselves in the Tax Court, and everyone has the right to legal representation, highlighted by the Miranda Rights and the Sixth Amendment.
Step-by-step explanation:
Regarding the unauthorized practice of law, statement a, "A CPA cannot express a legal opinion on a non-tax matter", is CORRECT. CPAs are typically trained and licensed in accounting and, unless they are also licensed attorneys, they should not provide legal opinions on matters outside of their expertise and licensure, including non-tax related legal matters to avoid the unauthorized practice of law.
However, CPAs may express opinions on tax matters, as long as their comments are confined to areas where accounting and tax law intersect and they don't venture into legal advice that requires a law license. It is also important to note that taxpayers do have the right to draft their contracts and represent themselves in court, including Tax Court, which makes options a and b from the other statements incorrect.
This self-representation is a principle upheld under the constitutional right to defend oneself in court. Lastly, the concept that everyone has the right to a lawyer is strongly protected, particularly in criminal cases, as emphasized in the Miranda Rights and by the Assistance of Counsel Clause of the Sixth Amendment.