According to the approach of the ABA Model Rules, when a lawyer joins a new firm there is a presumption that the lawyer comes to the new firm with knowledge of confidential information related to the cases handled by the lawyer's former firm. This presumption, however, is rebuttable.
However, Law.com is reporting today that the Court of Appeals for the 5th circuit has a case before it in which the issue is precisely whether that presumption should be irrebutable.
A finding that the presumption is irrebutable would be terrible in many ways. For individual lawyers, it would make it terribly difficult to find a new job because firms will not be willing to open their doors to lawyers who would then force the firms to give up current clients because of the conflicts the new lawyer's presence in the firm would create. For firms, it would mean that they would be subject to being disqualified just because a new lawyer in the firm is thought to have confidential information about a former client even if, in fact, the lawyer could show he or she did not.
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