It’s possible — but only under very strict circumstances. Here’s what you need to know about your lawyer’s duty of confidentiality and potential conflicts of interest
Theoretically yes, but that lawyer would need to be very careful how they go about it.
That’s because every lawyer owes a very strict duty of confidentiality to their clients, and that duty continues well after the lawyer is no longer acting for you — indeed, even beyond your death. A lawyer is bound to act solely in the interests of their client in any proceeding or transaction, and they must avoid any potential or actual conflict between the interests of current and former clients.
So, while technically a solicitor has no fiduciary duty to act in the best interest of an ex-client, they are still bound by the requirement not to disclose confidential information obtained from that client, or use such information in the advancement of another client’s interests. Where your former solicitor takes instructions from someone in a dispute against you, a conflict may very likely arise between their duty of confidentiality to you and their duty to their new client to use all of their knowledge and skill to advance that new client’s interests solely.
The reality is we lawyers often get an intimate peek behind the curtain of our client’s lives. Their finances, their personal lives, even the way they negotiate or make decisions may be revealed through the course of taking instructions and providing advice. That means that, if we subsequently take on the case of a new client against our old client, all or some of that information we obtained from or about the old client could potentially be used to advance the interests of the new client — to the detriment of the former client.
For that reason, lawyers need to tread very carefully indeed before taking instructions from new clients in circumstances where, by doing so, they may risk breaching their obligations to a former client.
However, there are some limited instances where solicitors can comfortably take instructions, despite potential conflicts of interest. One is where, after having been fully informed of the potential conflict of interest, the former client consents to the lawyer acting for the new client, notwithstanding such conflict. The most common example of this is where two parties to a commercial transaction engage one lawyer to act for both parties in circumstances where they are more or less on the same page. But even in those circumstances, the possibility of a conflict arising as a result of an unanticipated disagreement between the parties is ever present, and such circumstances can sometimes ultimately require the solicitor to cease acting for both parties as a result.
One circumstance in which your former legal representatives may be able to act against you is where the firm is able to confidently establish sufficient “information barriers” to ensure there can be no leakage of confidential information. Some larger law firms have hundreds of lawyers, often spread over various departments, offices, states and even countries. Just because one lawyer working in such a firm once acted for you in relation to, say, a family law dispute, that would not necessarily prevent a different lawyer at the same firm, who was not privy to any of your confidential information, from taking instructions against you in an entirely different proceeding. That is, provided a strict Chinese wall – also known as an information barrier or ethics wall – can be established to ensure there is no cross-fertilisation of confidential client information.
However, given the optics involved in taking instructions against a former client, and the risk that a conflict could potentially arise in such circumstances, even with the greatest of care, this approach is rarely adopted by law firms.
Published in Ocean Road Magazine 11 July 2025: Ocean Road Magazine
