ABA Family Legal Guide

Criminal Justice

Court Procedures

Evidence in Criminal Cases

How may I recognize and preserve evidence to help me at my trial?

Physical evidence--such as a gun or a piece of clothing--can be very important in helping a judge or a jury piece together what actually happened. These people were not there when the alleged crime took place. The physical evidence can provide a way to show that your version of the facts is correct.

You should preserve any items that might be useful as evidence, whether you think the evidence will help or harm your case. It is against the law to destroy evidence. In any event, let your lawyer determine whether the evidence is harmful. For example, you might believe that the prosecution will use a gun with your fingerprints as evidence against you in a shooting. But if your lawyer can show that the gun was too big or the trigger too hard to pull for someone of your size to have fired it, then the evidence will help your case. The only logical explanation then would be that you picked up the gun after the shooting. This may cause the jury to have a reasonable doubt about your guilt.