In Padilla v. Kentucky, the Supreme Court ruled in a 7-2 opinion that counsel for the defense must warn of the consequences of a plea of guilty for those who may face later deportation proceedings.  The court did not make a ruling as to the prejudice suffered by Mr. Padilla in this specific case, but remanded the case for further proceedings.

http://www.mysanantonio.com/news/local_news/239_drug-case_lawyers_given_potential_basis_for_appeals.html

The Bexar County District Attorney’s office has sent letters to over 230 criminal defense lawyers explaining that drug cases investigated between 2006 and 2009 by the Bexar County Sheriff’s Office may be tainted by perjury and falsified evidence.