Definition
A lawsuit in which two or more parties appear together on the same side — either as co-plaintiffs bringing a claim together, or as co-defendants sued together. The term describes the procedural posture of the action rather than any particular cause of action or theory of liability. A joint action on the plaintiff side unites multiple claimants whose interests or rights arise from a common transaction or relationship. A joint action on the defendant side unites multiple parties who are alleged to share responsibility for the same wrong or obligation.
Joint action is distinct from the underlying question of whether liability itself is joint, several, or joint and several. Two defendants may be sued in a joint action but face separate and independent obligations; conversely, parties may bear joint liability without being joined in the same proceeding.
Common Confusion
Joint action is often conflated with joint and several liability, but these are separate concepts. Joint action is procedural — it describes who is in the lawsuit. Joint and several liability is substantive — it describes the legal relationship among parties who owe a shared obligation. A joint action does not presuppose joint and several liability, and joint and several liability can exist between parties who are not joined in a single action. Researchers working in older sources must be alert to this slippage, since historical writers sometimes used "joint action" loosely to gesture at the underlying liability theory rather than the procedural alignment of parties.
Why It Matters in Research
The term does relatively light analytical work in modern practice, where joinder rules under the Federal Rules of Civil Procedure and their state equivalents have largely displaced the older common-law vocabulary around joint actions. A researcher encountering "joint action" in pre-twentieth-century pleading materials should understand that the term carried more technical weight at common law, where the rules governing who could be joined — and who was required to be joined — were considerably more rigid. Failure to bring all necessary joint parties into a common-law action could result in abatement, a trap that modern permissive and compulsory joinder rules largely eliminate.
In historical corpus research, "joint action" may appear in proximity to discussions of joint obligations, joint tenancy, joint tortfeasors, or partnership liability — not because the term encompasses those doctrines, but because those relationships frequently gave rise to joint actions. Treat the surrounding context as the guide to which doctrine is actually being discussed.
The Rapalje & Lawrence entry illustrates a common hazard in historical dictionaries: the headword launches into a series of related sub-entries (joint administrators, joint and several) without clearly demarcating where the definition of joint action ends and where digested case notes on adjacent topics begin. Researchers using that source should read carefully to avoid attributing doctrines from those adjacent entries to the core definition.
In employment and tort research, the phrase "joint action" sometimes appears in a different register entirely — describing coordinated conduct among multiple actors as a predicate for liability, as in civil rights doctrine under 42 U.S.C. § 1983 (where "joint action" between a private party and a state actor can establish the state action requirement). This usage is doctrinally unrelated to the procedural meaning and should not be conflated with it.
Historical Dictionary Support
All four source dictionaries agree on the core definition without meaningful variation: a joint action is one in which multiple parties are united as plaintiffs or defendants. Black's, Bouvier, and Burrill each state this in nearly identical terms. Burrill adds the qualifier "in practice," usefully flagging this as procedural vocabulary rather than substantive doctrine.
Rapalje & Lawrence diverge in presentation, packaging the joint action definition as a launching point for a cluster of related entries. This is more useful as a research index than as a standalone definition, and researchers should treat it accordingly.
None of the historical sources address the modern divergence between the procedural concept and the § 1983 "joint action" doctrine, which postdates all four dictionaries. That gap is significant for any researcher moving between historical and contemporary materials.
Encyclopedia Cross-Reference
Vicarious Liability and Joint Tort Liability — Joint and Several Liability (The Law Mind Torts & Personal Injury Encyclopedia) [torts_147]
Vicarious Liability and Joint Tort Liability — Partnership and Joint Venture Liability (The Law Mind Torts & Personal Injury Encyclopedia) [torts_152]
Joint Employer and Co-Employment Doctrine (The Law Mind Employment & Labor Law Encyclopedia) [employment_3]