Only a complete fucking moron would move legal data with torrents.
A lawyer is obligated to preserve his clients' confidences. When you store your information on somebody elses server or servers you are giving up custody and control over some of those confidences. In that situation you are entirely dependent upon the strength of your encryption.
That encryption might be good today or tomorrow, but how good will it be five years from now or ten years from now when quantum computing or the next best thing becomes available for codebreakers.
Don't risk a lawsuit from a pissed client!