Yes, they can. However, the preliminary hearing is rarely used as an opportunity to present defense witnesses (evidence). Unless evidence is offered as a affirmative defense (not merely a difference of opinion of what happened), it will likely be preserved for trial. Issues of credibility, inconsistent statements and other discrepancies are largely reserved for trial on the ultimate question: can the prosecutor prove the case beyond a reasonable doubt.
This is not intended as legal advice, nor does it establish or suggest the formation of the attorney-client relationship.
If you are talking about the preliminary examination, sometimes called the preliminary hearing, which takes place before a trial in a felony case, the answer is yes. However, the defense often chooses not to put on its own evidence as a tactical decision. Every case is different. But the preliminary examination is really the prosecution's show. They have to convince the court there is sufficient evidence to bind the case over for trial.
A good example for such use would be alibi. If there was a witness, or other proof (ATM camera) that you were somewhere else when the crime occurred, that would be a good time to bring it forward to assist the court in eliminating further wasted time in a trial.
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Assuming that you are referring to a preliminary hearing the answer in most jurisdictions would be yes it is permitted, but it would usually be a bad idea. Every case has to be considered on its own facts and only an attorney familar with the case and the facts should be making that decision. If you are referring not to a preliminary hearing but to a motions hearing or other proceeding, the considerations might be different, but the situation would still present a judgment call for the attorney.
This depends on the nature of the pre-trial hearing. If you are thinking of a preliminary hearing, the defense does have the right to call witnesses although it is rarely done. If there is an important defense witness that will likely not be around at the time of trial, it is not a bad idea to have the witness testify at the preliminary hearing and "lock in" their testimony. On the other hand if the DA chooses not to bring in a prosecution witness and chooses instead to elicit the information through a police office, the defense should likely not use the witness themselves at the preliminary hearing. If the witness becomes legally unavailable at the time of trial and they previously testified and there was an opportunity for cross-examination, the defense will then be stuck with the previous testimony being allowed before a jury. Each case is different and the decision to put on a witness at a preliminary hearing should be carefully considered.
As far as other pre-trial hearings are concerned, the defense may or may not be allowed to use witnesses. Evidence Code 402 hearings can be used at the court's discretion as an opportunity to present testimony in an effort to convince the judge to rule a certain way.