In an Illinois criminal felony case, the Defendant has a right to a preliminary hearing. The preliminary hearing is a court date at which the prosecution has the burden of showing that there is probable cause to believe that the Defendant has committed a felony. If the prosecution cannot convince the judge that there is probable cause, the judge will dismiss the charges against the Defendant.
Probable Cause is one of the lowest standards in the Illinois legal system, meaning that it is relatively easy for the prosecution to show that there is probable cause. Just because the judge finds probable cause it does not mean that the Defendant is guilty or has a bad case. In the overwhelming majority of felony cases filed in Illinois, the judge finds probable cause and the case continues.
To show probable cause at a preliminary hearing in Illinois, prosecutors will usually call a police officer to the witness stand and ask the officer a series of questions, with the goal of showing that the Defendant appears to be involved in some conduct that would constitute a felony. Illinois law allows hearsay testimony at a preliminary hearing, meaning that one police officer can appear and read the police report of another police officer, or a police officer can appear and say what a witness allegedly stated outside of court. That sort of hearsay testimony would generally not be allowed at trial, but it is allowed by Illinois courts at the preliminary hearing.
A benefit of the preliminary hearing for the Defendant is that the Defendant’s attorney can ask questions of the prosecution’s witnesses at the preliminary hearing, thereby locking them into a story that they cannot change later. Sometimes it is possible to ask questions at a preliminary hearing that the Defendant’s attorney would not be able to ask until Trial, and by learning that information early the case can be improved.
There are also situations where it is wise for the Defendant to waive (give up) the right to a preliminary hearing. That includes cases where the evidence is such that there is really no benefit in having the preliminary hearing, or cases where the benefit is outweighed by the Defendant’s desire not to have details of the case stated in open court. There are also other situations that are more technical in nature, relating to the ability of the prosecution to use preliminary hearing testimony at trial if a witness is unavailable for trial that should be considered as well.
If the preliminary hearing results in a finding of probable cause, or if the Defendant waives the preliminary hearing, then the case proceeds. If there is no finding of probable cause, then the court dismisses the charges.