Kinds of Arguments in Common Law

Overview: Legal vs. Philosophical Argumentation

• Lawyers “argue for a living.”

  • Goal: win on behalf of a cause or client.

  • Argument often has stakes (money, liberty, policy) beyond pure logical validity.

• Philosophers mainly pursue logical soundness (valid inference from premises → conclusion).

• Legal argument is not illogical, but routinely integrates:

  • Client-centered objectives.

  • Institutional constraints (procedure, jurisdiction, precedent).

  • Extra-logical considerations (policy, fairness, administrability).

Defining “Common Law”

• Term frequently used in 1L courses yet rarely unpacked.

• "Simple" definition: judge-made law.

  • Rules emerge from judicial decisions, not from an authoritative text (statute, constitution).

• Importance in curriculum:

  • Distinguished from statutory interpretation and constitutional analysis (covered elsewhere, different toolkit).

  • Core subjects where it dominates: Contracts, Torts, Property.

Four Rough Categories of Common-Law Arguments

(Instructor’s “rough cuts”; borders are porous, categories often overlap.)

1. Arguments from Precedent

2. Arguments from Public Policy

3. Arguments from Rights / Morality

4. Arguments from Administration / Administrability

Category 1 – Arguments from Precedent (Stare Decisis)

• Governing principle: stare decisis (“let the decision stand”).

  • Once a court decides X, later courts should follow X when materially similar facts arise.

  • Earlier decisions become precedents.

• Strength of the obligation varies by:

  • Court hierarchy (binding vs. persuasive precedent).

  • Jurisdictional tradition.

1920 Toaster Case (Hypothetical)

• Facts: Guest uses friend’s toaster → presses button normally → electrocuted.

• Lawsuit: Guest sues manufacturer.

• Holding of California Supreme Court (highest state court):

  • Rule: Privity requirement – only the purchaser can sue for defect.

  • Guest (non-purchaser) loses.

  • Decision date: 1920.

1950 Car Passenger Case (Hypothetical)

• Facts: Car passenger injured due to defective automobile.

• Lawsuit: Passenger sues car manufacturer.

• Defense’s argument from precedent:

  • The 1920 toaster precedent controls → non-purchaser cannot recover.

• Court’s dilemma:

  1. Follow precedent strictly → passenger loses.

  2. Distinguish or overrule → passenger may win.

Techniques Within Precedent-Based Arguing

• Facial application: “Facts the same, rule the same.”

• Distinguishing: Identify “salient differences” (product type, technology change, social context) so precedent is not truly “on point.”

• Direct challenge / overruling: Argue that the earlier case was wrongly decided or is obsolete (e.g., safety knowledge, modern economics).

Category 2 – Arguments from Public Policy

• Invites court to weigh social consequences of a rule.

• Can be deployed by either side; no inherent political valence.

Defense-Side Policy Argument (Car Case)

• If passengers can recover:

  • Damage payouts → higher manufacturer costs → higher car prices.

  • Possible regressive economic impact: low-income buyers hurt most.

  • Cars may become less affordable; harms social mobility.

Plaintiff-Side Policy Argument (Car Case)

• If passengers cannot recover:

  • Injured individuals bear medical bills, lost wages; may lack insurance.

  • Leads to uncompensated losses → social welfare burden → inequity.

Combining with Precedent

• Lawyers often weave policy into precedent analysis:

  • “Yes, Your Honor, you have a toaster precedent, but cars present different policy stakes (mass transportation, higher risks, etc.), so doctrine should evolve.”

Category 3 – Arguments from Rights / Morality (Mentioned, Not Yet Elaborated)

• Appeal to moral entitlements or inherent rights (e.g., bodily integrity, autonomy).

• Often overlaps with constitutional values or natural-law reasoning.

Category 4 – Arguments from Administration / Administrability (Mentioned, Not Yet Elaborated)

• Focus on institutional competence & efficiency:

  • Can courts administer the proposed rule without excessive cost or uncertainty?

  • Predictability, clarity, ease of application for lower courts and litigants.

Cross-Cutting Themes & Practical Takeaways

• Categories are heuristics for classroom discussion; real briefs blend them.

• Legal craftsmanship involves:

  1. Mapping facts to precedent.

  2. Crafting policy narratives.

  3. Invoking moral principles where persuasive.

  4. Assuring courts of manageable implementation.

• Mastery for students:

  • Recognize each argumentative “dial.”

  • Practice toggling among them depending on client goals and factual nuance.

• Institutional backdrop: Common-law evolution happens case by case, balancing stability (stare decisis) against responsiveness (policy, moral progress, administrability).

Ethical & Philosophical Implications

• Predictability vs. Justice: Strict precedent promotes consistency; flexible policy reasoning promotes tailored justice.

• Socio-economic distribution: Liability rules shift costs between manufacturers, consumers, victims.

• Judicial Role: Debate over whether judges should merely apply law (formalism) or consciously shape social outcomes (realism).

Numerical References Recap (LaTeX Format)

• Toaster decision year: 1920

• Car passenger decision year: 1950