As it stands now in Washington, lawyers can't knowingly offer false information in court, and they can't put their client on the witness stand if they know the client will lie.

An attorney who later realizes a client has lied and can't fix it -- by persuading the person to tell the truth, for example -- usually asks to be removed from the case to avoid becoming part of the deceit.

Examples of where the new rule would be overly detrimental to the attorney client relationship:

What if an arrested man persuades a judge to release him without bail, explaining that he lives with his mother and has a full-time job, and the lawyer later learns that neither is true? The lawyer would have to tell the judge -- probably ensuring that the client gets locked up, Rodriguez said.

Or what if the lawyer has to tell the judge that a client said something untrue on the witness stand? Prosecutors might be able to use the information to help their case, or it could prompt the judge to call a mistrial.

Defense attorneys say the new rule would discourage defendants from telling them anything for fear they might decide, even wrongly, that something is a lie. "It really destroys that sense of trust that clients need to have in their attorney," Trieweiler said. "There's no reason to create this rift."