Art. 1031.Incidental Demands Allowed

Every lawsuit starts with one claim — the principal demand, the plaintiff's original suit. But litigation rarely stays that simple. A defendant may have a claim of their own against the plaintiff. One defendant may have a claim against a co-defendant. A stranger to the suit may have a stake in its outcome. A defendant may need to pull in someone who owes reimbursement if the defendant loses. Louisiana groups every one of these add-on claims under a single label: the incidental demand.

Article 1031 sets the boundaries. Subsection A lets a party bring an incidental demand against an adverse party, a co-party, or a third person — covering every direction a claim can run within an ongoing suit. Subsection B then names the four devices the rest of this chapter builds out: reconvention (Louisiana's term for a counterclaim), cross-claims (a claim between co-parties), intervention (a third person joining the suit), and the demand against third parties (bringing in someone new who may owe the defendant reimbursement).

These four devices share a family resemblance — each rides along with, and depends on, the principal demand — but they work differently and follow separate rules. Reconvention runs between the existing plaintiff and defendant. A cross-claim runs between parties already on the same side. Intervention brings in an outsider who wants a role in the case. A third-party demand brings in an outsider the defendant wants to hold responsible. The articles that follow treat each on its own terms.