What should I tell my lawyer?

You should tell your lawyer the truth. Your lawyer has to know exactly what happened in order to defend you effectively. Tell your lawyer as many details as you can remember. Anything you tell your lawyer is confidential and will be kept secret, unless it applies to any continuing or future crime. The law refers to this as the attorney-client privilege. Your lawyer has ethical obligations to you as the client.
A lawyer also has an ethical obligation to the court. A lawyer may not lie to the court for you or knowingly offer a false defense. In practical terms, that means that if you tell your lawyer you did not commit the crime but were present when it happened, your lawyer cannot bring in alibi witnesses who will testify falsely that you were with them in another state when the crime took place. If you tell your lawyer that you did commit the crime, he or she is limited in the way he or she can present the case.
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