Are there penalties for withholding self-exculpatory evidence during a trial?

Question

Suppose a person is put on trial for a crime, but he has video evidence showing his innocence. Out of malice or spite of a personal nature towards his accuser, he allows the trial to proceed, and then at the last possible moment "discovers" and presents the evidence, leading to his acquittal and the accuser's extreme shock, dismay, and embarrassment.Are there any sanctions that could be applied to the defendant if the court were convinced he had withheld that evidence in order to prolong the trial?

Answer 1

Typically there is no duty for the defense to present evidence of a video prior to trial. A person would have to testify to creating the video to establish foundation for the video. Defense attorneys typically follow norms of listing witnesses who will testify for the prosecution to prepare rebuttal. It is the duty of the prosecution to find out why that person is testifying on the defendants' behalf. Exculpatory evidence is evidence that is contrary to what the prosecution's case is or weakens the prosecutions case but was discovered originally by the prosecution. So in definition, your scenario would not call the video used by the defendant as exculpatory evidence, just evidence. As for presenting the video at the end of trial, that is actually the norm. The defense presents its case after the prosecution does. There is no real motive to have a defendant hide their alibi from the prosecution but if that were the case and the defendant presented the video last minute, the prosecution would probably file a motion to retrieve the video and conduct analysis with an expert witness to see if the video were tampered with before motioning for a dismissal of charges.

The short answer is that the defendant would likely not be punished by trial fees for doing such a thing but would need to follow other procedures like having a witness present who recorded the video or handing the evidence over for analysis before, during or after the trial to the prosecution.