In its 7-2 decision, the high court ruled a federal appellate court "could not, on its own initiative" impose a longer sentence on defendants.
Michael Greenlaw was tried and convicted of several drug and gun charges in Minneapolis. In calculating his sentence, the trial court made a mistake, sentencing him to 10 years on a count that carried a mandatory 25-year minimum term. When Greenlaw appealed his case, the appellate court added 15 years to that count. However, because the government didn't appeal the original sentence, the appeals court couldn't impose more time, the Supreme Court ruled.
Under an "unwritten but longstanding rule, an appellate court may not alter a judgment to benefit a non-appealing party," Justice Ruth Bader Ginsburg wrote for the majority. "This court, from its earliest years, has recognized that."
Ginsberg was joined by Chief Justice John Roberts and Justices Antonin Scalia, Anthony Kennedy, David Souter and Clarence Thomas. Justice Stephen Breyer filed a concurring opinion but dissented, in part.
Justices Samuel Alito and John Paul Stevens dissented.
Courts, Alito said, must have the discretion to make exceptions to rules and "we should entrust the decision to initiate error correction to the sound discretion of the courts of appeals."