Lawyer-client exclusivity rule

The Lawyer-client exclusivity rule is the professional restriction that prevents one lawyer from representing both members of a divorcing couple. Its decisive consequence, as presented in the book, is that it can impose an adversarial structure on people who might otherwise cooperate: instead of sharing advice and limiting costs, the couple is separated into opposing legal camps, while the resulting conflict can benefit the lawyers.

Background: Cooperation within conflict

The example appears in an argument that apparent disputes need not be zero-sum. Even after a marriage ends, a couple may have shared reasons to cooperate, including their children’s welfare and the desire to avoid the expense of retaining two lawyers. The book contrasts this possibility with a system that does not let the couple begin by consulting one lawyer together.

How the rule works

In England and, until recently, throughout all fifty states of the United States, the law or, more precisely, lawyers’ professional code barred a lawyer from accepting both members of a couple as clients. One person could be accepted; the other would be turned away and left either without legal advice or obliged to seek another lawyer. The restriction therefore does more than allocate representation: it divides the couple before their dispute reaches court.

Adversarial consequences

Separate representation encourages each side to be understood as an “us” opposed to a “them,” even when the couple themselves do not feel hostile and have expressly agreed to seek an amicable divorce. The case is presented in court as “Smith versus Smith,” giving it an adversarial form regardless of the couple’s intentions. The rule thus converts a situation with potential for mutual cooperation into a zero-sum contest for the clients.

Incentives and significance

The book distinguishes the clients’ contest from the lawyers’ relationship to it. The couple bears the costs of the opposition, while the two professionals can benefit from the arrangement: their separation is described as a means of cooperation at the clients’ expense. The rule serves as a concrete illustration of how institutional practices may manufacture conflict rather than merely respond to it, and of how conduct framed as adversarial for one group can produce shared benefits for another.