Legal reasoning is not so much a "game" asit is "puzzle-solving".

An integral part of legal reasoning using precedents is the practiceof distinguishing. Distinguishing involves a precedent notbeing followed even though the facts of the later case fall within thescope of the ratio of the earlier case. As the later casefalls within the scope of the earlier ratio (i.e., within thescope of the rule), one might expect that the decision in the latercase must be the same (unless the court has the power to overrule theearlier case and decides to do so). In legal reasoning usingprecedents, however, the later court is free not to follow the earliercase by pointing to some difference in the facts between the twocases, even though those facts do not feature in theratio of the earlier case.

Here is a quicksummary of nine that I find important to the problem of legal reasoning.

By contrast, arguments of equality bite where the court in theoriginal case was confronted with a situation where the correctoutcome was indeterminate, i.e., where more than one outcome waspossible in light of the legally permissible arguments. This may bedue to each outcome being equally well supported by reason, or by theoutcomes being supported by different, incommensurable, values. Insome of these cases the law has closure rules to settle the matter,e.g. in favour of criminal defendants, but in others there are noclosure rules as to the appropriate substantive result to endorse. Apossible illustration of such indeterminacy is the position of aperson who quite innocently buys stolen goods. In some legal systemsthe purchaser acquires good title to those goods, whereas in others(such as the Common Law) she does not. Here, arguably, the merits ofthe two innocent parties (the purchaser and the original owner) are ona par, and all the law can do is choose which one is to prevail. Sowhere an outcome is underdetermined there are arguments of equalityfor later courts following the earlier decision rather than adoptingany of the other possible solutions. None of this, of course, is anargument for following earlier decisions that were wrongly decided,since these are cases where the earlier court did not make a mistake,but took one permissible option.

Chapter 1: What Legal Reasoning Is, and Why It Matters

This fact does not, however, support a doctrine of following earlierdecisions even when they are wrong, i.e., for having a strongpractice of stare decisis. If the earlier decision was wrongthen the person subject to it may have been treated more or lessfavourably than they should have been treated. If they were treatedmore favourably then clearly that should have been corrected (e.g. onappeal). If it was not corrected then the person had an undeservedslice of good fortune. But that a mistake was made in the earlier caseis not—in itself—an argument for repeating the mistake inthe later case. The first litigant did not deserve their outcome, evenif for reasons of the finality of legal processes they are entitled toretain it. Equality does not demand the repetition of mistakes. On theother hand, if the original litigant was treated less favourably thanthey deserved then again that mistake should be corrected if it can be(e.g. by appeal, or, if that is too late, by remedial legislation orby executive action such as pardon or ex gratia payments),but it is no reason for treating a later litigant unfavourably aswell. Taken in isolation from other considerations (such asexpectations and predictability), equality does not support thebindingness of incorrect decisions.

Lawyering and Legal Reasoning - Samford University

This is related to another point: if the underlying justificationfor a precedent is binding then it undermines the distinction betweenarguments from precedent and those by analogy. The ratioof the precedent sets the outer limit of what is binding onlater courts—i.e., what a later court is bound to either follow ordistinguish. Analogies (as will be argued below) aregrounded in the underlying rationale for earlier decisions, but they donot bind later courts. If the underlying justificationof precedents were binding, rather than the ratio, thenanalogies would be binding and legal reasoning would have a differentshape.