LEGAL PRINCIPLE: EVIDENCE LAW — Admissibility — Oral Evidence Varying Written Contract — Separate Oral Agreement Must Be Distinctly Pleaded
PRINCIPLE STATEMENT
Oral evidence cannot be used to contradict, alter, or vary a written contract. Any separate or subsequent oral agreement must be distinctly pleaded and specifically proved.
RATIO DECIDENDI (SOURCE)
Per Onu, JSC, in Arjay Ltd & Ors v. Airline Management Support Ltd (2003) NLC-1122000(SC) at p. 17; Paras B–C.
"The appellant, in effect, attempted to contradict, alter or vary by oral evidence a transaction or grant in writing. In this regard, attention must be drawn to section 131 of the Evidence Act. I think it is plain from the rules of pleadings and of evidence in support that any such separate or subsequent agreement must be distinctly pleaded and specifically proved."
EXPLANATION / SCOPE
The parol evidence rule prohibits oral variation of written contracts. The principle applies to contract law. A separate oral agreement must be pleaded and proved. The rule ensures certainty. The court will not admit oral evidence to vary a written agreement. The principle is well-established.
