Supreme Court justices are questioning whether defendants should expect their lawyers to advise them on all the possible consequences of a guilty plea before it is submitted to a court.

Jose Padilla wants his guilty plea to drug charges thrown out. The Honduras-born immigrant says he wouldn't have made the plea if his lawyer hadn't incorrectly told him it would not affect his immigration status. He now faces deportation.

Lawyer Stephen Kinnaird says bad advice on the collateral consequences of a guilty plea is a violation of the constitutional right of "effective assistance of counsel."

But prosecutor WM Robert Long Jr. said criminal attorneys' only constitutional duty is to advise defendants on guilt, innocence and sentencing when it comes to pleas.