From United States v. Boender, 2010 U.S. Dist. LEXIS 20670 (N.D. Ill. Mar. 8, 2010):

Unless limited by the U.S. Constitution, an Act of Congress, or a Supreme Court Rule, privileges are "governed by the principles of the common law as they may be interpreted by the courts of the United States in light of reason and experience." Fed. R. Evid. 501. The Seventh Circuit looks to Proposed Rule of Evidence 503 "as a source of general guidance regarding federal common law principles." United States v. BDO Seidman, LLP, 492 F.3d 806, 814-15 (7th Cir. 2007) (quoting In re Grand Jury Investigation, 399 F.3d 527, 532 (2d Cir. 2005)). ***

[A]lthough the privilege has an important place in our adversary system of litigation, "[t]he privilege takes flight if the relation is abused." Clark v. United States, 289 U.S. 1, 15 (1933) (Cardozo, J.).

One way in which a client may abuse the attorney-client relationship is by using the lawyer in order to further a crime or fraud. See, e.g., United States v. Zolin, 491 U.S. 554, 562-63 (1989) (the privilege ceases "to operate at a certain point, namely when the desired advice relates not to prior wrongdoing, but to future wrongdoing"); In re Sealed Case, 754 F.2d 395, 402 (D.C. Cir. 1985) (crime-fraud exception where the unknowing representation and advice of counsel assisted the defendant in an attempted cover-up). "The privilege is not good in itself. * * * Secrecy is useful to the extent it facilitates the candor necessary to obtain legal advice. The privilege extends no further." Matter of Feldberg, 862 F.2d 622, 627 (7th Cir. 1988); United States v. Hodge and Zweig, 548 F.2d 1347, 1355 (9th Cir. 1977) (Kennedy, J.) ("[A] quid pro quo is exacted for the attorney-client confidence: the client must not abuse the confidential relation by using it to further a fraudulent or criminal scheme * * *."). Thus, as the Supreme Court has noted, the "established exceptions" to the attorney client-privilege, "such as the crime-fraud exception * * * are consistent with the purposes of the privilege." Swidler & Berlin, 524 U.S. at 409-10; see also Glover v. Patten, 165 U.S. 394, 406 (1897) (no exclusion for communications that "are not within the reason of the rule requiring their exclusion").

To invoke the crime-fraud exception, "the party seeking to abrogate the * * * privilege must present prima facie evidence that 'gives colour to the charge' by showing 'some foundation in fact.'" *** If the challenging party meets this burden, the proponent of the privilege must "come forward with an explanation for the evidence offered against it." ... If the Court finds the explanation "satisfactory," then the privilege remains. *** Otherwise, "the seal of secrecy is broken." *** See also Sound Video Unlimited v. Video Shack, Inc., 661 F. Supp. 1482, 1486 (N.D. Ill. 1987) (party seeking to abrogate the privilege must establish a connection between the "communications at issue and the alleged offense"). Notably, for the exception to the evidentiary privilege to apply, the Government is not required to show that a privilege holder actually succeeded in committing a crime; the wrongdoing "need only have been the objective of the client's communication." United States v. Collins, 128 F.3d 313, 321 (6th Cir. 1997)***. Finally, it is the intent of the client, rather than the intent of the lawyer, that governs whether the crime-fraud exception applies.