Rules of Criminal Procedure, Rule 583 is called the Severance of Offenses or Defendants. This is usually filed when a particular Defendant does not wish to be tried with his co-defendant. Things the defense attorney should consider are:
The Court may order separate trials on separate offenses and separate trials for separate defendants provided it appears any party may be prejudiced by the offenses or defendants being tried together. For instance, suppose you have a co-defendant charged with sexual abuse of a minor and your client is only charged with some type of disorderly conduct in interfering with the arrest of the co-defendant. Why should your client be tried at the same time for a separate, distinguishable offense rather than be tried with the defendant charged with the sexual abuse of children. Even though many of the same witnesses will be called to testify in both cases, it is clearly not in your client’s best interest to be affiliated with a potential child abuser if your client is only charged with interference in making an arrest. Any request for severance must ordinarily be made in the omnibus pre-trial motion or it is considered waived. Therefore, whenever there are multiple defendants a good lawyer should determine within a short time after the preliminary hearing whether they can carve away his defendant to a separate and distinct trial.
