A preliminary hearing involves the judge, defendant, defence attorney, prosecuting attorney and witnesses. The preliminary hearing allows the judge to determine whether the prosecution has enough probable cause, or evidence against the defendant, for the case to proceed to trial.
The preliminary hearing gives the judge the opportunity to hear and evaluate the prosecution's reasons for wanting to bring a defendant to trial. If the judge finds that the evidence is insufficient, he can dismiss the case against the defendant. The judge can also set bail based on the evidence provided, and order that the case proceed to trial.
The preliminary hearing takes place after the arrest of a person, and before trial. It is not generally considered the best time for the defendant to testify or make any kind of statement. The opportunity for the defence to make a case will come when and if the case goes to trial.
The defendant may be given the right to waive a preliminary hearing. While this might result in a lower bond, there are negative consequences, as well. Waiving a preliminary hearing eliminates an opportunity for the defence to see the prosecution's witnesses, hear their statements and begin preparing a response for trial.