After the trial court enters judgment on a verdict in a criminal case and sentences the defendant, the defendant is a prisoner if he was not a prisoner already. The goal of the prisoner's attorney is to shorten the term of imprisonment.
In a direct appeal the prisoner's brief may state that the defendant requests resentencing. Resentencing is seldom accomplished by claims that the sentencing court should have believed or not believed a witness, or that the sentence is simply too severe. Claims that the sentence failed to take into account the defendant's potential for rehabilitation or that someone else received a lesser sentence for similar behavior are also unlikely to win. The appellate court can only read the motions and rulings in the trial court's file and read the transcripts of the trial and sentencing. The sentencing court has heard the witnesses speak, including the defendant if he testifies. The sentencing court has also watched the witnesses, and has watched the defendant even if the defendant has not testified. Because the sentencing court has an opportunity that the appellate court does not have, to hear and see the witnesses, the trial court has virtually limitless discretion to impose a sentence that does not exceed the maximum sentence allowed by law.
Resentencing is more readily granted as the result of a claim that the sentencing court has made some legal error that has nothing to do with how the witnesses testified. An example is a sentence that exceeds the maximum sentence allowed by law. Another example is the sentencing court's refusal to hear evidence that by law should be considered. In federal court, the Sentencing Guidelines computation is open to question. Basically any question of law has the potential to lead to resentencing.
Direct appeal is not the only proceeding that can lead to resentencing. A motion to reconsider sentence can lead to resentencing. Resentencing can be granted as the result of state post-conviction or federal habeas corpus proceedings.
