Rule 4:0.Application of Part Four.

Rule 4:0 sets the boundary for everything that follows in Part Four. Its rules on depositions, interrogatories, document production, and the rest apply to civil cases in the circuit courts. They also reach a defined set of special proceedings: separate maintenance, divorce, or annulment cases; eminent domain cases; and habeas corpus or coram nobis proceedings — all three of which get the narrower discovery scope spelled out in Rule 4:1(b)(5), with habeas and coram nobis proceedings carrying the additional requirement that no discovery is allowed at all without the court’s advance leave. Wherever Part Four uses the word “action,” it means any of these civil matters, whether the underlying claim sounds in law or in equity.

Rule 4:0(b) draws a second, equally important line: nothing in Part Four changes how evidence gets presented at trial. Courts still take evidence ore tenus — live, in open court — in claims at law, and by deposition in equitable claims, exactly as before these discovery rules existed. Part Four governs how parties gather information before trial, not how that information reaches the fact-finder once the case is heard.