What is the test for waiving privilege to testify in a personal injury case?

These considerations--which underlie "the fairness doctrine"--aim to prevent prejudice to a party and distortion of the judicial process that may be caused by the privilege-holder's selective disclosure during litigation of otherwise privileged information. Under the doctrine the client alone controls the privilege and may or may not choose to divulge his own secrets. But it has been established law for a hundred years that when the client waives the privilege by testifying about what transpired between her and her attorney, she cannot thereafter insist that the mouth of the attorney be shut. Hunt v. Blackburn, 128 U.S. 464, 470-71, 9 S.Ct. 125, 127, 32

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