The Supreme Court issued an opinion in Padilla v. Kentucky today (see previous posts on this case here and here).
As background, the petitioner, Jose Padilla, had been a lawful permanent resident of the United States over forty years (and served in the in the U.S. military during the Vietnam War) when he was indicted in 2001 on three drug counts related to the trafficking and possession of marijuana. He sought advice from his attorney, asking specifically about the consequences of a guilty plea. His attorney assured him that deportation was not a concern because of the length of time he had been in the country. But the advice from Padilla's attorney was wrong, and he was subject to deportation.
Justice Stevens delivered the 7-2 majority opinion (with Justice Alito filing a concurring opinion in which Chief Justice Roberts joined). Justice Scalia authored a dissenting opinion in which Justice Thomas joined.
The majority held that a lawyer is required under the Sixth Amendment to inform a client whether a plea carries a risk of deportation, but declined to find whether Padilla was prejudiced by his attorney's failure to do so in this case. As Justice Stevens explained:
We agree with Padilla that constitutionally competent counsel would have advised him that his conviction for drug distribution made him subject to automatic deportation. Whether he is entitled to relief depends on whether he has been prejudiced, a matter that we do not address.