“Can a family lawyer act against a former client? That is the issue at the heart of this motion. The lawyer for Ms. DeCorte acted for Mr. DeCorte in 2006. At the time, Mr. DeCorte was separating from his first wife. The issues in 2006 included a determination of income for purposes of calculating support. Now, 15 years later, the lawyer who acted for Mr. DeCorte is acting for his second wife. Issues in the current litigation include determination of income for purposes of calculating support. Can the lawyer act for the second wife, or is there a disqualifying conflict of interest?
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These are complex issues. There is no hard and fast rule that a lawyer can never act in opposition to a former client. That said, the integrity of the system will sometimes require that a lawyer refrain from taking on a file that pits him or her against someone he or she acted for in the past.
There is a clear tension in cases of this nature. On the one hand, the law recognizes the importance of litigants’ right to counsel of choice. On the other hand, that right is not absolute and is subject to reasonable limitations. A litigant cannot choose counsel that has a conflict of interest in circumstances that would detrimentally affect the administration of justice: see R. v. Hendrickson, [2002] O.J. No. 1982 (S.C.); R. v. Speid (1983), 1983 CanLII 1704 (ON CA), 43 O.R. (2d) 596 (C.A.); R. v. Robillard (1986), 1986 CanLII 4687 (ON CA), 28 C.C.C. (3d) 22 (Ont. C.A.); R. v. Brissett (2005), 2005 CanLII 2716 (ON SC), 74 O.R. (3d) 248 (S.C.).
In assessing whether there exists a disqualifying conflict of interest, the court must balance competing interests. On the one hand, the court must be concerned to maintain the high standard of the legal profession and the integrity of our system of justice. On the other hand, the court must recognize the strong countervailing value that a litigant should not be deprived of his or her choice of counsel without good cause.
In R. v. W.(W.) (1995), 1995 CanLII 3505 (ON CA), 25 O.R. (3d) 161 (C.A.), Doherty J.A. set out the test that a trial judge must apply in assessing an alleged conflict of interest, at pp. 18-19:
It is important to distinguish between the respective functions of a trial judge and an appellate court when faced with a conflict of interests claim. Where the issue is raised at trial, the court must be concerned with actual conflicts of interests and potential conflicts that may develop as the trial unfolds. In deciding whether counsel should be permitted to act for co-accused, trial judges must, to some degree, speculate as to the issues which may arise and the course the trial will take. The trial judges’ task is particularly difficult since they cannot be privy to the confidential discussions which may have passed between the clients and counsel and which may reveal the source of potential conflicts. Given those circumstances, trial judges must proceed with caution and when there is any realistic risk of a conflict of interests they must direct that counsel not act for one or perhaps either accused.
The test set out in W.(W.) is whether there is any realistic risk of a conflict of interest. This test is similar to the one set out by the Supreme Court of Canada in MacDonald Estate v. Martin, 1990 CanLII 32 (SCC), [1990] 3 S.C.R. 1235 (“MacDonald”) in which the Court held that a “possibility of real mischief” will warrant the removal of counsel. The term “mischief” in that case, at p. 1246, referred to “the misuse of confidential information by a lawyer against a former client.” Where it is shown that a lawyer was previously retained on a related matter, the onus will shift to the lawyer to prove that no information was imparted that could be relevant. On this point, Sopinka J. stated the following, at pp. 1260-1261:
In my opinion, once it is shown by the client that there existed a previous relationship which is sufficiently related to the retainer from which it is sought to remove the solicitor, the court should infer that confidential information was imparted unless the solicitor satisfies the court that no information was imparted which could be relevant. This will be a difficult burden to discharge. Not only must the court’s degree of satisfaction be such that it would withstand the scrutiny of the reasonably informed member of the public that no such information passed but the burden must be discharged without revealing the specifics of the privileged communication. Nonetheless, I am of the opinion that the door should not be shut completely on a solicitor who wishes to discharge this heavy burden.
The “heavy burden” resting upon counsel requires that a “reasonably informed member of the public” be satisfied that the new retainer will not give rise to a conflict of interest.”