Can my mother get her US citizenship back after being deported for a drug related offense?

The U. S. government cannot deport a U. S. citizen for a crime committed after the individual is naturalized, so I will assume that your mother was either a permanent resident or the crime was committed prior to her becoming a U. S. citizen. Drug transportation is treated very harshly under the U. S. immigration laws, and the fact that a few lawyers have already gone over her case and not encouraged her is an indication that she will not gain any immigration relief. There is no immigrant visa waiver that covers drug transportation. The best hope was probably trying to obtain a nonimmigrant waiver at the border based on emergent humanitarian reasons, but that was apparently turned down. Her case unfortunately does not look encouraging at all unless she is able to overturn the criminal conviction. Due to the limitations of the Lawyers.com Forums, Alan Lee, Esq.'s (the "Firm") participation in responding to questions posted herein does not constitute legal advice, nor legal representation of the person or entity posting a question. No Attorney/Client relationship is or shall be construed to be created hereby. The information provided herein by the Firm is general, and requires that the poster obtain specific legal advice from an attorney. The poster shall not rely upon the information provided herein as legal advice nor as the basis for making any decisions of legal consequence.