A lawyer can only adequately represent her client if she knows all the facts. On the other hand, a client may be wary of telling his attorney everything, for fear of it reflecting poorly on his case or that the attorney will turn around and spill the beans to prosecutors or the judge.
While there are legal protections in place to foster full communication between criminal defendants and their counsel and you should feel comfortable answering all of your attorney's questions honestly, these protections have their limitations. Here's what you need to know about attorney-client privilege in criminal cases, and when your lawyer might be required to breach it.
As a general rule, a client can refuse to disclose and prevent others from disclosing confidential communications between himself and his attorney. The privilege belongs to the client, and the attorney cannot waive it or breach it in most instances. The rule is designed to encourage a client to disclose all relevant information to his attorney, without fear that the information will become public or used against him.
As long as the communication occurred for the purpose of securing a legal opinion, legal services, or assistance in some legal proceeding, an attorney cannot inform on her client. So a criminal defense attorney cannot reveal what her client told her to law enforcement or the court. There are, however, a couple exceptions.
If the communication was made for the purpose of committing a crime or fraud, or in the furtherance of fraud or other crime, it is no longer protected by attorney-client privilege. So if the client is trying to use the attorney's services to commit or cover up a crime or fraud, the attorney is not only permitted, but in some instances required, to disclose information to prevent the crime or fraud.
The regulations can vary by state -- some allow an attorney to disclose information in order to prevent death or serious bodily injury, others require an attorney to disclose information in order to prevent or rectify financial crimes or frauds. In some extreme cases, a lawyer cannot allow her client to testify falsely on the stand in a criminal case. Sometimes the rules can be thought of based on time: discussion of past crimes is generally covered by attorney-client privilege, while discussion of future crimes may not be.
In most cases, your lawyer is not going to turn you in. And if you've been charged with a crime, you're better off contacting and consulting with an experienced criminal defense attorney.