In a short but excellent decision, the Board of Immigration Appeals addressed a scenario that has plagued immigration practitioners for years. Who bears the burden of proving removability when a person has been granted lawful permanent residence and returns from a trip abroad, but the Department of Homeland Security (DHS) alleges that they were never entitled to residency in the first place? In that case, may the DHS charge the returning resident with inadmissibility, even if he does not fit into the narrow grounds listed in section 101(a)(13)(C) of the INA? No - it cannot. A returning resident who does not fall into these narrow grounds can only be charged with deportability, not inadmissibility. This is important, because the DHS bears the burden of proving deportability, while a noncitizen bears the burden of proving admissibility.
The full text of Matter of Pena can be found here: http://www.justice.gov/eoir/file/478111/download