In a published decision, the Board of Immigration Appeals upheld the suspension of an attorney who repeatedly had his legal assistant impersonate him during telephonic hearings. The Board agreed that the attorney had assisted in the unauthorized practice of law, and upheld a 16 month suspension from practice before the immigration agencies and a 7 year ban on telephonic appearances.
The full text of Matter of P. Singh, Attorney can be found here: http://www.justice.gov/eoir/file/623226/download