Antecedents are the life history and previous convictions of a defendant in a criminal case.

When a defendant is being sentenced for a crime, the court will be told his or hers antecedents, and this information is likely to be important in deciding the sentence the defendant should receive. If a defendant pleads not guilty, his or her previous convictions are not usually made known to the jury during the trial. This is to prevent prejudice against the defendant, although it is argued that if the defendant has previous convictions for similar types of offence, this should be part of the evidence given at the trial.